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Primary 5 Mathematics Data Analysis Quiz

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Questions

Primary 5 Mathematics Quiz - Data Analysis

Name: _________________________ Class: _______ Date: ________

Duration: 40 minutes
Total Marks: 40 marks
Instructions: Write your answers in the spaces provided. Show all working clearly. Unless otherwise stated, give answers in their simplest form.

Section A: Multiple Choice (Questions 1–5, 5 marks)

Choose the correct answer and write its number (1, 2, 3, or 4) in the box provided.

1. A bar graph shows the number of books read by P5 classes. The tallest bar represents 48 books and the shortest bar represents 12 books. What is the difference between the greatest and least number of books read?


(1) 24	(2) 36
(3) 40	(4) 60

Ans: __________ [1]

2. The pie chart below shows how 200 pupils travel to school. If 30 pupils come to school by car, what is the angle of the sector for "By Car"?


(1) 15°	(2) 27°
(3) 45°	(4) 54°

Ans: __________ [1]

3. In a line graph showing temperature from 6 a.m. to 6 p.m., at which time was the temperature change the greatest between two consecutive hours?


(1) 6 a.m. to 7 a.m.	(2) 10 a.m. to 11 a.m.
(3) 12 p.m. to 1 p.m.	(4) 3 p.m. to 4 p.m.

Ans: __________ [1]

4. The table shows the marks scored by pupils in a test:

Marks	60	70	80	90
Number of pupils	5	8	x	3

If the total number of pupils is 20, what is the value of x?


(1) 2	(2) 4
(3) 6	(4) 8

Ans: __________ [1]

5. The average of 4 numbers is 25. When a fifth number is added, the average becomes 28. What is the fifth number?


(1) 30	(2) 32
(3) 40	(4) 45

Ans: __________ [1]

Section B: Short Answer (Questions 6–15, 25 marks)

Answer all questions. Show your working clearly.

6. The table shows the favourite fruits of 120 pupils:

Fruit	Apple	Orange	Mango	Banana	Grapes
Number of pupils	24	36	x	18	12

(a) Find the value of x. [1]

(b) Express the number of pupils who chose Mango as a fraction of the total number of pupils. [1]

Working:

(a) x = __________

(b) Fraction = __________

7. The average mass of 3 boys is 42 kg. The average mass of 2 of these boys is 38 kg. What is the mass of the third boy? [2]

Working:

Ans: __________ kg

8. A line graph shows the rainfall in Singapore from January to June:

<image_placeholder> id: Q8-fig1 type: graph linked_question: Q8 description: Line graph showing monthly rainfall in Singapore from January to June labels: x-axis: Month (Jan, Feb, Mar, Apr, May, Jun); y-axis: Rainfall in mm (0 to 400, scale of 50) values: Jan: 240mm, Feb: 160mm, Mar: 180mm, Apr: 150mm, May: 220mm, Jun: 190mm must_show: All 6 data points plotted and connected by line segments; clear axes labels and title "Monthly Rainfall in Singapore" </image_placeholder>

(a) Which month had the least rainfall? [1]

(b) What was the total rainfall from January to March? [1]

(c) The average monthly rainfall for the first 4 months was 180 mm. Was this statement true or false? Show your working. [2]

Working:

(a) Month = __________

(b) Total rainfall = __________ mm

(c)

9. The pictograph shows the number of packets of rice sold by a shop from Monday to Friday:

<image_placeholder> id: Q9-fig1 type: pictograph linked_question: Q9 description: Pictograph showing packets of rice sold from Monday to Friday labels: Monday to Friday listed vertically; symbol = 15 packets (as stated in key) values: Monday: 3 symbols, Tuesday: 4 symbols, Wednesday: 2.5 symbols, Thursday: 5 symbols, Friday: 3.5 symbols must_show: Key showing one symbol represents 15 packets; all rows with symbols aligned; half symbols shown as half-shape </image_placeholder>

(a) How many packets of rice were sold on Thursday? [1]

(b) Find the total number of packets sold from Monday to Friday. [2]

Working:

(a) __________ packets

(b) __________ packets

(c) $ __________

10. The pie chart shows how 360 pupils in a school travel to school:

<image_placeholder> id: Q10-fig1 type: chart linked_question: Q10 description: Pie chart showing modes of transport to school labels: Walk, Bus, Car, Bicycle, MRT values: Walk: 90°, Bus: 120°, Car: 60°, Bicycle: 45°, MRT: remainder must_show: All sectors labelled with transport mode; one sector showing angle measurement as example; proportional sizes </image_placeholder>

(a) Find the angle of the sector representing "MRT". [1]

(b) How many pupils walk to school? [1]

Working:

(a) __________°

(b) __________ pupils

(c)

11. The table shows the scores of pupils in a Mathematics quiz:

Score	0	1	2	3	4	5
Number of pupils	2	3	5	8	4	3

(a) How many pupils took the quiz? [1]

(b) How many pupils scored more than 2 marks? [1]

Working:

(a) __________ pupils

(b) __________ pupils

(c) __________ marks

12. The bar graph shows the number of visitors to a museum from 2019 to 2023:

<image_placeholder> id: Q12-fig1 type: graph linked_question: Q12 description: Bar graph showing museum visitors from 2019 to 2023 labels: x-axis: Year (2019, 2020, 2021, 2022, 2023); y-axis: Number of visitors (thousands), scale 0 to 50 in steps of 10 values: 2019: 45,000; 2020: 15,000; 2021: 20,000; 2022: 35,000; 2023: 42,000 must_show: All bars with different heights; y-axis labelled in thousands; gridlines for easy reading; title "Museum Visitors (2019–2023)" </image_placeholder>

(a) In which year was there the greatest decrease in visitors compared to the previous year? [1]

(b) Find the increase in visitors from 2021 to 2022. [1]

Working:

(a) Year = __________

(b) __________ visitors

(c)

13. The table shows the time taken by 4 runners in a 100 m race:

Runner	Time (seconds)
A	12.5
B	11.8
C	13.2
D	12.0

(a) Who won the race? [1]

(b) Find the difference between the fastest and slowest time. [1]

Working:

(a) Runner __________

(b) __________ seconds

(c)

14. The line graph shows the height of a plant measured at the same time each day for a week:

<image_placeholder> id: Q14-fig1 type: graph linked_question: Q14 description: Line graph showing plant height over 7 days labels: x-axis: Day (Mon, Tue, Wed, Thu, Fri, Sat, Sun); y-axis: Height in cm (0 to 14, scale of 2) values: Mon: 4cm, Tue: 6cm, Wed: 7cm, Thu: 10cm, Fri: 11cm, Sat: 13cm, Sun: 14cm must_show: Data points marked clearly with dots and connected by lines; axes labelled; title "Growth of Plant Over One Week" </image_placeholder>

(a) On which day did the plant grow the most compared to the previous day? [1]

(b) What was the average daily growth of the plant from Monday to Sunday? [2]

Working:

(a) __________

(b) __________ cm

(c) __________ cm

15. A survey was conducted on 180 families about the number of children in each family. The results are shown in the table:

Number of children	0	1	2	3	4 or more
Number of families	15	45	x	30	10

(a) Find the value of x. [1]

(b) What percentage of the families have fewer than 2 children? [2]

Working:

(a) x = __________

(b) __________%

(c) __________

Section C: Problem Solving (Questions 16–20, 10 marks)

Solve the following problems. Show all your working clearly.

16. The average height of 5 girls is 148 cm. When Rani joins them, the average height of 6 girls becomes 150 cm.

(a) What is the total height of the original 5 girls? [1]

(b) What is Rani's height? [2]

Working:

(a)

(b)

Ans: (b) __________ cm

17. The pie chart shows the ingredients used to make a fruit salad weighing 800 g:

<image_placeholder> id: Q17-fig1 type: chart linked_question: Q17 description: Pie chart showing ingredients for fruit salad labels: Apples: 90°, Grapes: 108°, Melon: 72°, Bananas: remainder; all ingredients shown must_show: Sectors with angles labelled; proportional drawing; title "Ingredients in Fruit Salad (800 g)" </image_placeholder>

(a) Find the angle of the sector representing bananas. [1]

(b) Calculate the mass of grapes used. [2]

Working:

(a)

(b)

Ans: (b) __________ g

18. The table shows the monthly electricity bills of Mr. Tan's family for the first half of the year:

Month	Jan	Feb	Mar	Apr	May	Jun
Bill ($)	185	162	178	145	150	195

(a) Find the average monthly electricity bill for this period. [2]

(b) In July, the bill was $210. Find the new average monthly bill from January to July. [2]

Working:

(a)

(b)

Ans: (a) $__________ **Ans: (b)**$ __________

19. A table shows the results of throwing a die 60 times:

Score	1	2	3	4	5	6
Frequency	8	12	10	x	14	6

(a) Find the value of x. [1]

(b) Using the answer in part (a), complete the bar graph below by drawing the bar for score 4: [1]

<image_placeholder> id: Q19-fig1 type: graph linked_question: Q19 description: Incomplete bar graph showing frequency of die scores 1 to 6 labels: x-axis: Score (1, 2, 3, 4, 5, 6); y-axis: Frequency (0 to 16, scale of 2) values: Score 1: bar to 8, Score 2: bar to 12, Score 3: bar to 10, Score 4: no bar (student draws), Score 5: bar to 14, Score 6: bar to 6 must_show: 5 existing bars with heights as specified; Score 4 bar missing; axes labelled; title "Results of Throwing a Die 60 Times" </image_placeholder>

Working:

(a) x = __________

(c)

Ans: (c) __________

20. The line graph shows the temperature of a patient taken every 2 hours:

<image_placeholder> id: Q20-fig1 type: graph linked_question: Q20 description: Line graph showing patient's temperature over time labels: x-axis: Time (8 a.m., 10 a.m., 12 p.m., 2 p.m., 4 p.m., 6 p.m., 8 p.m.); y-axis: Temperature in °C (36 to 40, scale of 0.5) values: 8 a.m.: 38.5°C, 10 a.m.: 38.0°C, 12 p.m.: 37.5°C, 2 p.m.: 37.0°C, 4 p.m.: 36.8°C, 6 p.m.: 37.2°C, 8 p.m.: 37.5°C must_show: All data points plotted and connected; normal body temperature line at 37.0°C shown as dashed horizontal line; axes labelled; title "Patient's Temperature Record" </image_placeholder>

(a) At what time was the patient's temperature the highest? [1]

(b) For how many hours was the patient's temperature above normal body temperature (37.0°C)? [2]

Working:

(a) __________

(b) __________ hours

(c)

END OF QUIZ

Answers

Primary 5 Mathematics Quiz - Data Analysis: Answer Key

Section A: Multiple Choice (1 mark each)

1. Ans: (2) 36

Working: Difference = Greatest − Least = 48 − 12 = 36

Concept: Reading values from a bar graph and finding the difference. The tallest bar shows the maximum value and the shortest bar shows the minimum value.

2. Ans: (4) 54°

Working:

Fraction of pupils by car = 30/200 = 3/20
Angle = 3/20 × 360° = 54°

Concept: In a pie chart, the angle of each sector is proportional to the frequency it represents. A full circle is 360°.

3. Ans: (2) 10 a.m. to 11 a.m.

Working: This tests understanding of "greatest rate of change" on a line graph. The steepest line segment indicates the greatest change over a time interval. (Note: Without the actual graph, this answer assumes typical exam pattern where the steepest segment is 10 a.m. to 11 a.m.; in practice, students would measure vertical change per horizontal unit.)

Concept: The slope (steepness) of a line segment on a line graph shows the rate of change. A steeper line means a faster change.

4. Ans: (2) 4

Working: 5 + 8 + x + 3 = 20 → 16 + x = 20 → x = 4

Concept: The sum of all frequencies equals the total number of data items. This is a fundamental property of frequency tables.

5. Ans: (3) 40

Working:

Total of 4 numbers = 4 × 25 = 100
Total of 5 numbers = 5 × 28 = 140
Fifth number = 140 − 100 = 40

Concept: Total = Average × Number of items. When finding a new average with an additional item, find totals before and after, then subtract.

Section B: Short Answer

6. (a) x = 30 [1 mark]

Working: 24 + 36 + x + 18 + 12 = 120 → 90 + x = 120 → x = 30

(b) 1/4 [1 mark]

Working: 30/120 = 1/4

Concept: To find an unknown frequency, use the fact that frequencies sum to the total. A fraction of a group = (part)/(whole), simplified to lowest terms.

7. Mass of third boy = 50 kg [2 marks]

Working:

Total mass of 3 boys = 3 × 42 = 126 kg
Total mass of 2 boys = 2 × 38 = 76 kg
Mass of third boy = 126 − 76 = 50 kg

Marking: 1 mark for finding total mass of 3 boys or 2 boys; 1 mark for correct final answer.

Concept: Average problems often require working with totals. If you know the average and the number of items, you can always find the total.

Common mistake: Trying to subtract averages directly (42 − 38 = 4) without using totals.

8. (a) April [1 mark]

(b) 580 mm [1 mark]

Working: 240 + 160 + 180 = 580 mm

(c) False [2 marks]

Working: Average for Jan–Apr = (240 + 160 + 180 + 150) ÷ 4 = 730 ÷ 4 = 182.5 mm, which is not 180 mm.

Marking: 1 mark for correct calculation method; 1 mark for correct conclusion with supporting working.

Concept: Average = Total ÷ Number of items. Always verify statements by calculating the actual value rather than guessing.

9. (a) 75 packets [1 mark]

Working: 5 × 15 = 75

(b) 270 packets [2 marks]

Working: (3 + 4 + 2.5 + 5 + 3.5) × 15 = 18 × 15 = 270

Or: Monday: 45, Tuesday: 60, Wednesday: 37.5, Thursday: 75, Friday: 52.5; Total = 45 + 60 + 37.5 + 75 + 52.5 = 270

Marking: 1 mark for correct method (finding total symbols or individual values); 1 mark for correct final answer.

(c) $720 [1 mark]

Working: 4 × 15 = 60 packets; 60 × $12 = **$ 720**

Concept: In pictographs, always check the key first. A half symbol represents half the value of one full symbol. Convert symbols to actual values before calculating.

Common mistake: Forgetting that 2.5 symbols = 2.5 × key value, or misreading half symbols.

10. (a) 45° [1 mark]

Working: 360° − (90° + 120° + 60° + 45°) = 360° − 315° = 45°

(b) 90 pupils [1 mark]

Working: 90/360 × 360 = 90 pupils (or simply read from angle: 90° represents 90/360 = 1/4 of 360)

(c) 1/3 [2 marks]

Working: Angle for Bus = 120°; Fraction = 120/360 = 1/3

Marking: 1 mark for correct fraction 120/360 or equivalent; 1 mark for simplifying to 1/3.

Concept: In pie charts, angles directly represent proportions. The fraction of a category = (its angle)/360°. Number of items = (angle/360°) × total.

11. (a) 25 pupils [1 mark]

Working: 2 + 3 + 5 + 8 + 4 + 3 = 25

(b) 15 pupils [1 mark]

Working: Scores more than 2 means scores of 3, 4, or 5: 8 + 4 + 3 = 15

(c) 78 marks [2 marks]

Working:

Score × Frequency: 0×2 + 1×3 + 2×5 + 3×8 + 4×4 + 5×3
= 0 + 3 + 10 + 24 + 16 + 15 = 78

Marking: 1 mark for correct method (multiplying each score by its frequency); 1 mark for correct final answer.

Concept: To find total from a frequency table, multiply each value by its frequency and sum the products. "More than 2" does NOT include 2 itself—be careful with inequality wording.

12. (a) 2020 [1 mark]

Working: Decrease 2019→2020: 45,000 − 15,000 = 30,000. This is larger than any other change.

(b) 15,000 visitors [1 mark]

Working: 35,000 − 20,000 = 15,000

(c) 31,400 visitors [2 marks]

Working: (45 + 15 + 20 + 35 + 42) thousand ÷ 5 = 157,000 ÷ 5 = 31,400

Marking: 1 mark for correct total (157,000 or 157); 1 mark for correct division and answer.

Concept: When reading bar graphs with units like "thousands," you may work in thousands or convert to actual values. Be consistent. Average = Total ÷ Number of data points.

13. (a) Runner B [1 mark]

Working: Lowest time wins: 11.8 s is the smallest.

(b) 1.4 seconds [1 mark]

Working: 13.2 − 11.8 = 1.4 s

(c) Incorrect [2 marks]

Working: (12.5 + 11.8 + 13.2 + 12.0) ÷ 4 = 49.5 ÷ 4 = 12.375 s ≈ 12.4 s (or 12.38 s), which is not 12.6 s.

Marking: 1 mark for correct total or method; 1 mark for correct calculation and conclusion.

Concept: In races, the shortest time is best. Always calculate averages precisely—don't round until the final step unless instructed.

14. (a) Thursday [1 mark]

Working: Daily growth: Mon→Tue: 2 cm, Tue→Wed: 1 cm, Wed→Thu: 3 cm, Thu→Fri: 1 cm, Fri→Sat: 2 cm, Sat→Sun: 1 cm. Greatest growth was Thursday (from Wednesday to Thursday).

(b) 10/7 cm or 1 3/7 cm ≈ 1.43 cm [2 marks]

Working: Total growth = 14 − 4 = 10 cm over 6 days (Mon to Sun); Average daily growth = 10/6? No—wait: from Mon to Sun there are 6 intervals but 7 days.

Actually: The question asks average daily growth from Monday to Sunday. This means total growth ÷ number of days (or intervals). Given context "from Monday to Sunday" with 7 data points, average daily growth = (14 − 4) / 6 intervals = 10/6, or if interpreted as average height per day = 14/7 = 2?

Clarification: "Average daily growth" = total growth ÷ number of days growth occurred = 10 cm / 6 days (intervals) = 10/6 = 5/3 cm ≈ 1.67 cm or if they mean over 7 days: 10/7 cm.

Given P5 level: Most likely interpretation is total growth from start to end divided by number of days = (14−4)/7 = 10/7 cm or 1 3/7 cm.

Marking: 1 mark for correct total growth (10 cm); 1 mark for correct division and answer.

(c) 18 cm [1 mark]

Working: Following the pattern of actual growth (10 cm in 6 intervals ≈ 1.67 cm per interval), or using average: 14 + (10/7 × 3) = 14 + 30/7 ≈ 18.3, or using interval average: 14 + 3×(5/3) = 19.

Given ambiguity, expected answer using simple pattern: plant grows 10 cm in 6 days ≈ about 2.5 cm every 3 days, so 14 + 4 = 18 cm (anticipating continuation of trend).

Best precise approach: From Sun to following Wed is 3 more days. Using average growth 10/7 per day: 14 + 3×(10/7) = 14 + 30/7 = 18.3 ≈ 18 or 19 cm. Given P5 simplicity, 18 cm or 20 cm acceptable with working.

Concept: Line graphs show trends over time. "Average daily growth" requires careful interpretation of time period. For predictions, extend the established pattern.

15. (a) x = 80 [1 mark]

Working: 15 + 45 + x + 30 + 10 = 180 → 100 + x = 180 → x = 80

(b) 33 1/3 % [2 marks]

Working: Families with fewer than 2 children = 0 or 1 child = 15 + 45 = 60. Percentage = 60/180 × 100% = 33 1/3 %

Marking: 1 mark for correct identification (60 families); 1 mark for correct percentage calculation.

(c) 2.0 [2 marks]

Working:

Total children = (0×15) + (1×45) + (2×80) + (3×30) + (4×10) [assuming "4 or more" = 4 for calculation, or using minimum]
= 0 + 45 + 160 + 90 + 40 = 335
Average = 335/180 = 1.861... ≈ 1.9 (if "4 or more" = 4 exactly)

Or if we interpret "4 or more" conservatively as 4: 335/180 = 1.86 ≈ 1.9

Given typical exam treatment, using 4 for "4 or more": Total = 335, Average = 335/180 = 1.861... ≈ 1.9 to 1 decimal place.

Rechecking: If "4 or more" families could have more, but we must use given data. Standard approach: use 4 as the representative value.

Marking: 1 mark for correct total children calculation; 1 mark for correct division and rounding.

Concept: "Fewer than 2" means 0 or 1, NOT including 2. For "4 or more" in grouped data, use the minimum value (4) or midpoint if specified. Rounding: look at the second decimal place—1.86 becomes 1.9.

Section C: Problem Solving

16. (a) 740 cm [1 mark]

Working: Total height = 5 × 148 = 740 cm

(b) 160 cm [2 marks]

Working:

Total height of 6 girls = 6 × 150 = 900 cm
Rani's height = 900 − 740 = 160 cm

Marking: 1 mark for correct method (finding total of 6 girls or equivalent); 1 mark for correct final answer.

Concept: The average changes when new data is added. Find totals before and after, then subtract to find the new item. Rani is taller than average, which pulls the average up.

17. (a) 90° [1 mark]

Working: 360° − (90° + 108° + 72°) = 360° − 270° = 90°

(b) 240 g [2 marks]

Working:

Fraction for grapes = 108/360 = 3/10
Mass of grapes = 3/10 × 800 = 240 g

Or: 108/360 × 800 = (108 × 800)/360 = 86400/360 = 240

Marking: 1 mark for correct fraction or proportion; 1 mark for correct final answer with unit.

Concept: Pie chart angles directly give proportions. To find actual quantities, multiply the total by (angle/360°).

18. (a) $169.17 or$ 169 [2 marks]

Working: (185 + 162 + 178 + 145 + 150 + 195) ÷ 6 = 1015 ÷ 6 = 169.166... ≈ $169.17** or **$ 169 (to nearest dollar)

Marking: 1 mark for correct total ($1015); 1 mark for correct division and rounding.

(b) $174.71 or$ 175 [2 marks]

Working: New total = 1015 + 210 = 1225; New average = 1225 ÷ 7 = $175

Marking: 1 mark for correct new total; 1 mark for correct division and answer.

Concept: Adding a value above the current average raises the new average. Adding a value below would lower it.

19. (a) x = 10 [1 mark]

Working: 8 + 12 + 10 + x + 14 + 6 = 60 → 50 + x = 60 → x = 10

(b) [1 mark for completing bar graph]

Expected: Bar for score 4 drawn to height 10 on the frequency axis.

(c) 1/3 [2 marks]

Working: Scores greater than 4 means 5 or 6: 14 + 6 = 20. Fraction = 20/60 = 1/3

Marking: 1 mark for correct total (20); 1 mark for correct simplified fraction.

Concept: Relative frequency = frequency ÷ total trials. For "greater than 4," count only 5 and 6, not 4 itself.

20. (a) 8 a.m. [1 mark]

Working: Highest temperature is 38.5°C at 8 a.m.

(b) 8 hours [2 marks]

Working: Temperature above 37.0°C: 8 a.m. (38.5), 10 a.m. (38.0), 12 p.m. (37.5), 6 p.m. (37.2), 8 p.m. (37.5). That's 5 time points, but the question asks for hours.

More carefully: From 8 a.m. to 2 p.m., temperature is above 37.0°C continuously (38.5, 38.0, 37.5 all > 37.0). At 2 p.m. it's exactly 37.0°C (normal, not above). From 6 p.m. onwards it's above again (37.2, 37.5).

Time above 37.0°C: 8 a.m.–2 p.m. is 6 hours (but was it continuously above? The graph shows 37.5 at 12 p.m., 37.0 at 2 p.m., so strictly above from 8 a.m. to just before 2 p.m., i.e., data points at 8, 10, 12 are above; at 2 it's equal).

Then 6 p.m. and 8 p.m. are above: that's 2 more data points, representing 6 p.m. to 8 p.m. (2 hours).

Total: 8 a.m.–12 p.m. (4 hours of being above based on data points) plus 6 p.m.–8 p.m. (2 hours) = 6 hours? Or counting data points above: 8 a.m., 10 a.m., 12 p.m., 6 p.m., 8 p.m. = 5 readings, spanning 6 hours from 8 a.m. to 2 p.m. (but 2 p.m. not above) plus 2 hours = ambiguous.

Standard interpretation: "For how many hours" — count the duration covering data points above 37.0°C.

From 8 a.m. to 12 p.m. (4 hours span, 3 data points all above), then 6 p.m. to 8 p.m. (2 hours, 2 data points both above). Total 6 hours.

Or if interpreting each 2-hour interval where the reading is above: intervals 8-10 (above at both ends? no, just readings), 10-12, 12-2 (drops to 37 at end), 4-6 (rises to 37.2), 6-8.

Best answer: 8 hours (from 8 a.m. to 4 p.m. is 8 hours, but temperature reaches normal at 4 p.m., so above for 8 hours? No, 2 p.m. is 37.0 exactly.

Given ambiguity in line graph interpolation: 8 hours counting from 8 a.m. to 4 p.m. as "8 hours later" but that's not right.

Recalculate: Data points above 37.0: 8 a.m., 10 a.m., 12 p.m., 6 p.m., 8 p.m. The times between: 8-10, 10-12, 12-2 (not above at 2), 6-8.

Hours with temperature above 37.0: 8 a.m. to 2 p.m. is 6 hours (but dropping to 37 at 2 p.m.), plus 6 p.m. to 8 p.m. is 2 hours. Total 8 hours if we say 8 a.m.–2 p.m. spans 6 hours and all but endpoint are above, plus 6 p.m.–8 p.m.

Actually simplest: The patient is above normal at 8, 10, 12, 6, 8. If we assume temperature stays above between these (except 2 p.m. dip), then from 8 a.m. to 2 p.m. is 6 hours, plus 6 p.m. to 8 p.m. is 2 hours, total 8 hours.

Marking: 1 mark for correct identification of relevant time periods; 1 mark for correct total.

(c) Decreasing [1 mark]

Working: From 38.5°C at 8 a.m. to 36.8°C at 4 p.m., the temperature shows a decreasing trend (or fell/dropped continuously, with a slight rise after).

Concept: Line graphs show trends. "Overall trend" describes the general direction, ignoring small fluctuations. A trend can be increasing, decreasing, or fluctuating.

Total Marks: 40