Percent — Multiple Choice Questions

0.75 as percentage is:

1. 0.75%

2. 75%

3. 7.5%

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

Answer

To convert a decimal into percentage, multiply it by 100 and write the sign of percentage.

⇒ (0.75 × 100)%

⇒ 75%

Hence, option 2 is the correct option.

4 : 5 as percentage is:

1. 80%

2. 8%

3. 0.8%

4. 40%

Answer

Writing the ratio 4 : 5 as a fraction and then multiplying the fraction by 100 and writing the percentage sign :

⇒ 4 : 5

$\Rightarrow \dfrac{4}{5}$

$\Rightarrow \left(\dfrac{4}{5} \times 100\right)$%

$\Rightarrow \dfrac{400}{5}$%

⇒ 80%

Hence, option 1 is the correct option.

80% of 2 kg is:

1. 1600 g

2. 160 g

3. 16 g

4. 320 g

Answer

The given quantity is in kilogram, whereas all the options are in gram. So, 2 kg is first converted into gram, as the answer and the options must be in the same unit.

Converting 2 kg into grams :

2 kg = 2 × 1000 g = 2000 g.

80% of 2000 g

$\Rightarrow \dfrac{80}{100} \times 2000 \text{ g}\\[1em] \Rightarrow \dfrac{160000}{100} \text{ g}\\[1em] \Rightarrow 1600 \text{ g}$

Hence, option 1 is the correct option.

400 - 40% of 400 is:

1. 160

2. 240

3. 120

4. 360

Answer

⇒ 40% of 400

$\Rightarrow \dfrac{40}{100} \times 400\\[1em] \Rightarrow \dfrac{16000}{100}\\[1em] \Rightarrow 160$

∴ 400 − 40% of 400 = 400 − 160 = 240.

Hence, option 2 is the correct option.

80% of 500 - 30% of 500 is:

1. 750

2. 600

3. 250

4. none of these

Answer

⇒ 80% of 500 − 30% of 500

$\Rightarrow \dfrac{80}{100} \times 500 - \dfrac{30}{100} \times 500$

⇒ 400 - 150

⇒ 250

Hence, option 3 is the correct option.

800 is increased by 50%, the increase is:

1. 1200

2. 400

3. 600

4. 850

Answer

The increase is 50% of 800.

$\Rightarrow \dfrac{50}{100} \times 800\\[1em] \Rightarrow \dfrac{40000}{100}\\[1em] \Rightarrow 400$

Hence, option 2 is the correct option.

1600 is decreased by 25%, the decreased number is:

1. 1200

2. 200

3. 400

4. 2000

Answer

Decrease in it = 25% of 1600

= $\dfrac{25}{100} \times 1600$

= $\dfrac{40000}{100}$

= 400

Decreased number = 1600 − 400 = 1200.

Hence, option 1 is the correct option.

80 is increased by 50% of it, the increased number is:

1. 40

2. 100

3. 130

4. 120

Answer

Increase in it = 50% of 80

= $\dfrac{50}{100} \times 80$

= $\dfrac{4000}{100}$

= 40

Increased number = 80 + 40 = 120.

Hence, option 4 is the correct option.

500 is decreased by 20% of it, the decreased number is:

1. 600

2. 480

3. 400

4. 450

Answer

Decrease in it = 20% of 500

= $\dfrac{20}{100} \times 500$

= $\dfrac{10000}{100}$

= 100

Decreased number = 500 − 100 = 400.

Hence, option 3 is the correct option.

50% of 20 - 20% of 50 is equal to:

1. 1

2. 30%

3. 0

4. none of these

Answer

⇒ 50% of 20 − 20% of 50

$\Rightarrow \dfrac{50}{100} \times 20 - \dfrac{20}{100} \times 50$

⇒ 10 - 10

⇒ 0

Hence, option 3 is the correct option.