Percentage — Multiple Choice Questions

What per cent of 850 is 36?

1. 6%

2. 8%

3. $4\dfrac{4}{17}$%

4. 12%

Answer

Required percentage = $\left(\dfrac{36}{850} \times 100\right)$%

$= \dfrac{3600}{850}$%

$= \dfrac{72}{17}$%

$= 4\dfrac{4}{17}$%

Hence, option 3 is the correct option.

What per cent of 65 is 78?

1. 5%

2. 13%

3. 120%

4. 113%

Answer

Required percentage = $\left(\dfrac{78}{65} \times 100\right)$%

$= \dfrac{7800}{65}$%

= 120%

Hence, option 3 is the correct option.

If 15% of x = 9, then x = ?

1. 20

2. 30

3. 135

4. 60

Answer

15% of x = 9

$\Rightarrow \dfrac{15}{100} \times x = 9\\[1em] \Rightarrow x = \dfrac{9 \times 100}{15}\\[1em] \Rightarrow x = \dfrac{900}{15}\\[1em] \Rightarrow x = 60$

Hence, option 4 is the correct option.

$6\dfrac{2}{3}$% when expressed as a ratio, is:

1. 20 : 3

2. 9 : 2

3. 1 : 15

4. none of these

Answer

⇒ $6\dfrac{2}{3}$% = $\dfrac{20}{3}$%

$\Rightarrow \dfrac{20}{3} \times \dfrac{1}{100}\\[1em] \Rightarrow \dfrac{20}{300}\\[1em] \Rightarrow \dfrac{1}{15}\\[1em] \Rightarrow 1 : 15$

Hence, option 3 is the correct option.

$16\dfrac{2}{3}$% when expressed as a fraction, is:

1. $\dfrac{50}{3}$

2. $\dfrac{1}{6}$

3. $\dfrac{2}{3}$

4. none of these

Answer

⇒ $16\dfrac{2}{3}$% = $\dfrac{50}{3}$%

$\Rightarrow \dfrac{50}{3} \times \dfrac{1}{100}\\[1em] \Rightarrow \dfrac{50}{300}\\[1em] \Rightarrow \dfrac{1}{6}$

Hence, option 2 is the correct option.

6.5, when expressed as a percentage, is:

1. 65%

2. 650%

3. 6.5%

4. 0.65%

Answer

To convert a decimal into a percentage, multiply it by 100 and put the % sign.

⇒ 6.5

⇒ (6.5 × 100)%

⇒ 650%

Hence, option 2 is the correct option.

$\dfrac{3}{5}$, when expressed as a percentage, is:

1. 60%

2. 6%

3. 0.6%

4. 600%

Answer

To convert a fraction into a percentage, multiply it by 100 and put the % sign.

$\Rightarrow \dfrac{3}{5}$

$\Rightarrow \left(\dfrac{3}{5} \times 100\right)$%

$\Rightarrow \dfrac{300}{5}$%

$\Rightarrow 60$%

Hence, option 1 is the correct option.

What percent is 27 paise of ₹ 1.80?

1. 20%

2. 15%

3. $\dfrac{3}{2}$%

4. none of these

Answer

We know, ₹ 1 = 100 paise, so ₹ 1.80 = (1.80 × 100) paise = 180 paise.

Required percentage = $\left(\dfrac{27}{180} \times 100\right)$%

$= \dfrac{2700}{180}$%

= 15%

Hence, option 2 is the correct option.

What per cent is 48 cm of 1.5 m?

1. 32%

2. 72%

3. 64%

4. 46%

Answer

We know, 1 m = 100 cm, so 1.5 m = (1.5 × 100) cm = 150 cm.

Required percentage = $\left(\dfrac{48}{150} \times 100\right)$%

$= \dfrac{4800}{150}$%

= 32%

Hence, option 1 is the correct option.

What per cent is 175 g of 2.5 kg?

1. 14%

2. 21%

3. 7%

4. 28%

Answer

We know, 1 kg = 1000 g, so 2.5 kg = (2.5 × 1000) g = 2500 g.

Required percentage = $\left(\dfrac{175}{2500} \times 100\right)$%

$= \dfrac{17500}{2500}$%

= 7%

Hence, option 3 is the correct option.

The price of a bicycle is reduced from ₹ 4000 to ₹ 3500. The percentage decrease in the price is:

1. 7.5%

2. 8.5%

3. 12.5%

4. $14\dfrac{2}{7}$%

Answer

Original price = ₹ 4000 and reduced price = ₹ 3500.

Decrease in price = ₹ (4000 − 3500) = ₹ 500.

Percentage decrease = $\left(\dfrac{\text{Decrease}}{\text{Original price}} \times 100\right)$%

$= \left(\dfrac{500}{4000} \times 100\right)$%

$= \dfrac{50000}{4000}$%

= 12.5%

Hence, option 3 is the correct option.

80% of teachers in a school are females and the number of male teachers is 25. The number of female teachers is:

1. 90

2. 100

3. 115

4. 125

Answer

Let the total number of teachers be x.

Percentage of female teachers = 80%.

Percentage of male teachers = (100 − 80)% = 20%.

Then, 20% of x = 25

$\Rightarrow \dfrac{20}{100} \times x = 25\\[1em] \Rightarrow x = \dfrac{25 \times 100}{20}\\[1em] \Rightarrow x = 125$

Number of female teachers = 80% of 125

$= \dfrac{80}{100} \times 125\\[1em] = \dfrac{10000}{100}\\[1em] = 100$

Hence, option 2 is the correct option.

A mixture of milk and water contains 8 parts of milk and 2 parts of water. The percentage of milk in the mixture is:

1. 8%

2. 20%

3. 40%

4. 80%

Answer

Total parts in the mixture = 8 + 2 = 10.

Out of 10 parts, milk = 8 parts.

Percentage of milk in the mixture = $\left(\dfrac{8}{10} \times 100\right)$%

$= \dfrac{800}{10}$%

= 80%

Hence, option 4 is the correct option.

An alloy contains 35% zinc, 20% copper and rest nickel. In 1.5 kg of alloy, the quantity of nickel is:

1. 825 g

2. 765 g

3. 675 g

4. 575 g

Answer

Percentage of zinc and copper = (35 + 20)% = 55%.

Percentage of nickel = (100 − 55)% = 45%.

We know, 1 kg = 1000 g, so 1.5 kg = 1500 g.

Quantity of nickel in 1.5 kg of alloy = 45% of 1500 g

$= \dfrac{45}{100} \times 1500\\[1em] = \dfrac{67500}{100}\\[1em] = 675 \text{ g}$

Hence, option 3 is the correct option.