QUIZ ON PERCENTAGE

Problem 1 :

A survey of 40 children showed that 25% liked playing football. How many children not liked playing football ?

a) 90       b) 60         c) 30           d) none of these

Solution :

Number of children = 40

Number of children who are liking to play football = 25%

= 40 × 25/100

= 1000/10

= 10      

To find children not liked playing football :

 = 40 – 10

= 30

So, 30 children not liked playing football.

Hence option c) is correct.

Problem 2 :

8% children of a class of 25 like getting wet in the rain. How many children do not like getting wet in the rain.

a) 20       b) 22       c) 23       d) none of these

Solution :

8%children of a class of 25 like getting wet in the rain.

= 8/100 ×25

= 200/100

= 2

Children of a class of 25 do not like getting wet in the rain.

= 25 – 2

= 23

So, 23 children do not like getting wet in the rain.

Hence option c) is correct.

Problem 3 :

Rahul bought a sweater and saved $ 20 when a discount of 25% was given. What was the price of the sweater before the discount ?

a) $30        b) $40           c) $60        d) $80

Solution :

Let the price of the sweater before the discount be ‘x’.

Hence, 25% of x = 20

(25/100) × x = 20

1/4 × x = 20

x = 20 × 4

x = 80 

So, the price of the sweater before the discount is 80.

Hence option d) is correct.

Problem 4 :

Out of 15,000 voters in a constituency, 60% voted. Find the number of voters who did not vote.

a) 9000      b) 6000      c) 3000    d) none of these

Solution :

Total voters = 15,000

Percentage of voted candidates = 60%

Number of voters = 15000 × (60/100)

= 900000/100

= 9000

Who did not vote = 15000 – 9000

= 6000

Hence, 6000 candidates did not vote.

Hence option b) is correct.

Problem 5 :

Meeta saves $400 from her salary. If this is 10% of her salary. What is her salary ?

a) 4000       b) 6000       c) 3000     d) none of these

Solution :

Let Meeta salary be ‘x’.

Meeta saves the salary =  $400

10% of x = 400

400 = (10/100) × x

400 = x/10

400 × 10 = x

4000 = x

Hence, Meeta salary will be 4000.

Hence option a) is correct.

Problem 6 :

A local cricket team played 20 matches in one season.  It won 25% of them. How many matches did they lose?

a) 12     b) 14        c) 16        d) none of these

Solution :

A local cricket team played 20 matches in one season.

It won 25%

= 25/100 × 20

= 500/100

= 5

20 matches in one season = 20 – 1

= 19

To find matches did they lose = 19 – 5

= 14

So, 14 matches did they lose.

Hence option b) is correct.

Problem 7 :

A school team won 6 games this year against 4 games won last year. What is the per cent increase ?

a) 75%       b) 50%     c) 60%     d) none of these

Solution :

Given that, a school team won 6 games this year against 4 games won last year.

Increase in number of wins = 6 – 4

= 2

Hence, per cent increase = (2/4) × 100

= 1/2 × 100

= 50%

Hence, 50% per cent increase.

Hence option b) is correct.

Problem 8 :

The number of illiterate persons in a country decreased from $50 to $100 in 10 years. What is the percentage of decrease ? 

a) 30%       b) 50%      c) 331/3%      d) none of these

Solution :

Decrease in percentage = (original count  - new count)/original count × 100

= (150 – 100)/150 × 100

= (50/150) × 100

= 5000/150

= 33.3%

So, percentage of decrease is 33.3%.

Hence option c) is correct.

Problem 9 :

Cost of an item is $50. It was sold with a profit of 12%. Find the selling price.

a) $56        b) $60          c) $70    d) none of these

Solution :

Cost of an item = $50.

It was sold with a profit = 12%

Profit amount = 50 × (12/100)

= 600/100

= $6

To find the selling price :

Selling price = Cost price + Profit amount

= $50 + $6

= $56

So, selling price is 56.

Hence option a) is correct.

Problem 10 :

How much will an item cost if 10% discount is given on the marked price $100

a) 90         b) 110      c) 95       d) 85

Solution :

Item cost = 10% discount

$100 is the 100%

10% discount means 90% of it is considered as the cost.

Marked price = $100

= (90/100) × 100

= 9000/100

= 90

So, the cost of the product after discount is $90.

Hence option a) is correct.