08. Percentage of an Amount (Practice Questions)

NOTE:

Additional question must include:

• expressing amounts as a percentage of another
• percentages greater than 100% e.g. increase in value

---

Q1

Express $150$ as a percentage of $200$

Answer: $75\%$

Wrong answers:

$80 \%$

$65 \%$

$70 \%$

Workings:

$\dfrac{150}{200}=\dfrac{75}{100} = 75 \%$

1 mark

---

Q2

Express $18$ as a percentage of $20$

Answer: $90\%$

Wrong answers:

$80 \%$

$95 \%$

$93.3 \%$

Workings:

$\dfrac{18}{20}=\dfrac{9}{10} = 0.9 = 90 \%$

1 mark

---

Q3

Express $64$ as a percentage of $96$

Answer: $66 . \dot{6}\%$

Wrong answers:

$75 \%$

$80 \%$

$60 \%$

Workings:

$\dfrac{64}{96}=\dfrac{8}{12} = \dfrac{2}{2} = 0.\dot{6} = 66.\dot{6} \%$

1 mark

---

Q4

Express $125$ as percentage of $500$

Answer: $25 \%$

Wrong answers:

$30 \%$

$33.\dot{3} \%$

$20 \%$

Workings:

$\dfrac{125}{500}=\dfrac{25}{100} = 25\%$

1 mark

---

Q5

Express $12$ as a percentage of $25$

Answer: $48 \%$

Wrong answers:

$50 \%$

$35 \%$

$44 \%$

Workings:

$\dfrac{12}{25}=\dfrac{24}{50}= \dfrac{48}{100} = 48\%$

1 mark

---

Q6

Calculate $110 \%$ of $200$

Answer: $220$

Wrong answers:

$210$

$225$

$180$

Workings:

$110\% = 1.1$

$1.1\times200 = 220$

1 mark

---

Q7

Calculate $400 \%$ of $18$

Answer: $72$

Wrong answers:

$80$

$64$

$104$

Workings:

$400\% = 4$

$4\times 18 = 72$

1 mark

---

Q8

Calculate $250 \%$ of $206$

Answer: $515$

Wrong answers:

$484$

$528$

$495$

Workings:

$250\% = 2.5$

$2.5\times 206 = 515$

1 mark

---

Q9

Calculate $112.5 \%$ of $40$

Answer: $45$

Wrong answers:

$48$

$50$

$44$

Workings:

$112.5\% = 1.125$

$1.125\times 40 = 45$

1 mark

---

Q10

Calculate $145 \%$ of $16$

Answer: $23.2$

Wrong answers:

$25$

$24.4$

$22.8$

Workings:

$145\% = 1.45$

$1.45\times 16 = 16$

2 marks

---

Q11

Melvin wants to see how far he can run in half an hour.

On his first attempt, he runs $5.0$ km.

On his second attempt, he runs $5.6$ km.

What is his improvement in distance, expressed as a percentage?

Answer: $112 \%$

Wrong answers:

$105 \%$

$120 \%$

$115 \%$

Workings:

$\dfrac{5.6}{5.0}=\dfrac{56}{50}=\dfrac{112}{100}=112 \%$

1 mark

---

Q12

Jill has two buckets of water.

The larger of the two buckets can hold $25$ litres.

The smaller bucket can hold $34\%$ of the volume of the larger bucket.

How many litres of water can the smaller bucket hold?

ANSWER: $8.5$ litres

Wrong answers:

$10$ litres

$9.2$ litres

$6.4$ litres

Workings:

$34\% =0.34$

$0.34\times25=8.5$

2 marks

---