Secondary 1 Mathematics Semestral Assessment 2 (End of Year) Paper 2

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TuitionGoWhere Exam Practice (AI) - SA2 Mathematics Secondary 1

School: TuitionGoWhere Secondary School (AI)
Subject: Mathematics
Level: Secondary 1
Paper: SA2 Practice Paper (Version 2 of 5)
Duration: 60 minutes
Total Marks: 60
Name: __________________________
Class: __________
Date: ______________

Instructions:

1. Answer all questions in the spaces provided.
2. Show all working clearly.
3. Calculators may be used.
4. Write your answers in the units given.

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Section A: Short Answer (Questions 1–10) [20 marks]

1. [2 marks] Write the ratio $12 : 18 : 30$ in its simplest form.

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2. [2 marks] Express $45$ as a percentage of $120$.

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3. [2 marks] A recipe uses flour and sugar in the ratio $3 : 2$. If $150$ g of flour is used, how many grams of sugar are needed?

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4. [2 marks] Solve the inequality $-4x > 12$. Illustrate your answer on the number line below.

Image pending generation: diagram for Q4.

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5. [2 marks] A machine packs rice at $500$ g per second. How many $2$ kg bags can be filled in $10$ minutes?

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6. [2 marks] The price of a book increased from \8$to$$10$. Find the percentage increase.

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7. [2 marks] In a class of $40$ students, $16$ walk to school. Calculate the percentage of students who walk to school.

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8. [2 marks] The ratio of boys to girls in a club is $5 : 7$. If there are $35$ boys, how many girls are there?

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9. [2 marks] Solve $-2y \leq 10$ and state the solution.

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10. [2 marks] A car travels at $15$ m/s. How far does it travel in $2$ minutes? Give your answer in metres.

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Section B: Calculation and Problem Solving (Questions 11–16) [24 marks]

11. [3 marks] The number of red marbles is three times the number of blue marbles. There is an increase of $50\%$ in the number of blue marbles. If the number of red marbles remains the same, find the overall percentage change in the total number of marbles.

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12. [4 marks] Bags of coffee are filled at a rate of $250$ g per second. Each bag weighs $1.5$ kg. (a) How many bags can be filled in $1$ hour? [2] (b) If the rate is increased by $20\%$, how many bags can be filled in $1$ hour? [2]

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13. [4 marks] The table below shows the favourite sports of $80$ students.

Sport	Number of students
Football	28
Badminton	20
Swimming	16
Cycling	12
Others	4

(a) Calculate the percentage of students who chose Football. [2] (b) Hence, find the angle representing Swimming in a pie chart. [2]

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14. [3 marks] Solve the inequality $3 - 2k < 9$ and illustrate the solution on the number line below.

Image pending generation: diagram for Q14.

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15. [5 marks] A shop sold $200$ shirts in January. In February, sales decreased by $15\%$. In March, sales increased by $25\%$ compared to February. (a) Find the number of shirts sold in February. [2] (b) Find the number of shirts sold in March. [2] (c) Find the overall percentage change from January to March. [1]

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16. [5 marks] The ratio of money saved by Ali, Bob and Cai is $2 : 3 : 5$. If Cai saved \120$ more than Ali, find the total amount saved by all three.

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Section C: Extended Response (Questions 17–20) [16 marks]

17. [4 marks] The number of stickers in Box A is twice that in Box B. The number of stickers in Box B increases by $60\%$. Find the percentage increase in the total number of stickers if the number in Box A remains unchanged.

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18. [4 marks] A water tank is filled at a rate of $3$ litres per minute. (a) How many litres are filled in $25$ minutes? [2] (b) Another tank is filled at $0.1$ litres per second. Which tank is filled faster? Show your working. [2]

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19. [4 marks] The ratio of apples to oranges in a basket is $4 : 5$. After $12$ apples are added, the ratio becomes $2 : 1$. Find the original number of apples and oranges.

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20. [4 marks] The table shows the time taken by 4 students to run $100$ m.

Student	Time (s)
Dan	14.2
Eve	13.8
Fay	15.1
Gem	14.9

(a) Find the average speed of Eve in m/s. [2] (b) Who is the slowest runner? Give a reason. [2]

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TuitionGoWhere Exam Practice (AI) - SA2 Mathematics Secondary 1 (Version 2) Answer Key

Total Marks: 60

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Section A: Short Answer (Q1–10)

Q1 [2 marks]
Simplest form: divide each term by HCF of 12, 18, 30 which is 6.
$12 \div 6 = 2$, $18 \div 6 = 3$, $30 \div 6 = 5$.
Answer: $2 : 3 : 5$
(Marks: 1 for correct division, 1 for final ratio)

Q2 [2 marks]
$\frac{45}{120} \times 100\% = 37.5\%$
Answer: $37.5\%$
(Marks: 1 for fraction, 1 for percentage)

Q3 [2 marks]
Ratio flour : sugar = $3 : 2$. Flour = $150$ g $\Rightarrow$ 1 unit = $150 \div 3 = 50$ g.
Sugar = $2 \times 50 = 100$ g.
Answer: $100$ g
(Marks: 1 for unit value, 1 for sugar)

Q4 [2 marks]
$-4x > 12 \Rightarrow x < -3$ (divide by $-4$, reverse sign).
Number line: open circle at $-3$, arrow left.
(Marks: 1 for $x < -3$, 1 for correct number line)

Q5 [2 marks]
$10$ min = $600$ s. Total mass = $500 \times 600 = 300\,000$ g = $300$ kg.
Bags = $300 \div 2 = 150$.
Answer: $150$
(Marks: 1 for conversion and total, 1 for bags)

Q6 [2 marks]
Increase = $10 - 8 = 2$. $\frac{2}{8} \times 100\% = 25\%$.
Answer: $25\%$
(Marks: 1 for change, 1 for percentage)

Q7 [2 marks]
$\frac{16}{40} \times 100\% = 40\%$.
Answer: $40\%$
(Marks: 1 for fraction, 1 for percentage)

Q8 [2 marks]
Boys : girls = $5 : 7$. Boys = $35 \Rightarrow$ 1 unit = $7$. Girls = $7 \times 7 = 49$.
Answer: $49$
(Marks: 1 for unit, 1 for girls)

Q9 [2 marks]
$-2y \leq 10 \Rightarrow y \geq -5$.
Answer: $y \geq -5$
(Marks: 1 for solve, 1 for reverse sign)

Q10 [2 marks]
$2$ min = $120$ s. Distance = $15 \times 120 = 1800$ m.
Answer: $1800$ m
(Marks: 1 for time conversion, 1 for distance)

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Section B: Calculation and Problem Solving (Q11–16)

Q11 [3 marks]
Let blue = $x$, red = $3x$, total = $4x$.
New blue = $1.5x$, red unchanged = $3x$, new total = $4.5x$.
Change = $\frac{4.5x - 4x}{4x} \times 100\% = 12.5\%$ increase.
Answer: $12.5\%$ increase
(Marks: 1 setup, 1 new total, 1 percentage)

Q12 [4 marks]
(a) $1$ h = $3600$ s. Total = $250 \times 3600 = 900\,000$ g = $900$ kg. Bags = $900 \div 1.5 = 600$. [2]
(b) New rate = $250 \times 1.2 = 300$ g/s. Total = $300 \times 3600 = 1\,080\,000$ g = $1080$ kg. Bags = $1080 \div 1.5 = 720$. [2]
Answers: (a) $600$, (b) $720$

Q13 [4 marks]
(a) $\frac{28}{80} \times 100\% = 35\%$. [2]
(b) Swimming fraction = $\frac{16}{80} = 0.2$. Angle = $0.2 \times 360^\circ = 72^\circ$. [2]
Answers: (a) $35\%$, (b) $72^\circ$

Q14 [3 marks]
$3 - 2k < 9 \Rightarrow -2k < 6 \Rightarrow k > -3$.
Number line: open circle at $-3$, arrow right.
(Marks: 1 for isolate, 1 for $k>-3$, 1 for line)

Q15 [5 marks]
(a) Feb = $200 \times 0.85 = 170$. [2]
(b) Mar = $170 \times 1.25 = 212.5 \approx 213$ shirts (if whole). [2]
(c) Change = $\frac{212.5 - 200}{200} \times 100\% = 6.25\%$ increase. [1]
Answers: (a) $170$, (b) $212.5$, (c) $6.25\%$ increase

Q16 [5 marks]
Ali : Bob : Cai = $2 : 3 : 5$. Cai – Ali = $3$ units = \120 \Rightarrow$1 unit =$$40$. Total =$10$units =$$400$. Answer:$$400$
(Marks: 2 ratio setup, 2 unit value, 1 total)

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Section C: Extended Response (Q17–20)

Q17 [4 marks]
Let B = $x$, A = $2x$, total = $3x$.
New B = $1.6x$, A = $2x$, new total = $3.6x$.
Increase = $\frac{3.6x - 3x}{3x} \times 100\% = 20\%$.
Answer: $20\%$ increase
(Marks: 1 setup, 1 new, 1 calc, 1 answer)

Q18 [4 marks]
(a) $3 \times 25 = 75$ litres. [2]
(b) Tank 2: $0.1$ L/s = $6$ L/min. $6 > 3$, so Tank 2 faster. [2]
Answers: (a) $75$ L, (b) Tank 2

Q19 [4 marks]
Apples : oranges = $4 : 5$. Let apples = $4u$, oranges = $5u$.
After: $(4u+12) : 5u = 2 : 1 \Rightarrow 4u+12 = 10u \Rightarrow 6u = 12 \Rightarrow u = 2$.
Apples = $8$, oranges = $10$.
Answer: apples $8$, oranges $10$
(Marks: 1 setup, 2 solve, 1 answer)

Q20 [4 marks]
(a) Eve speed = $100 \div 13.8 \approx 7.25$ m/s. [2]
(b) Slowest = Fay (15.1 s, largest time). [2]
Answers: (a) $7.25$ m/s, (b) Fay

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Common mistakes flagged:

• Forgetting to reverse inequality when dividing by negative.
• Using new value as denominator in percentage change.
• Wrong unit conversion (g/kg, s/min).
• Ratio "twice" misread as inverse.