# Comparing Quantities Chapter 8 Class 8 Maths NCERT Textbook With Solutions PDF

NCERT Solutions for Class 8 Maths Chapter 8′ PDF Quick download link is given at the bottom of this article. You can see the PDF demo, size of the PDF, page numbers, and direct download Free PDF of ‘Ncert Class 8 Maths Chapter 8 Exercise Solution’ using the download button.

### Chapter 8:Comparing Quantities

#### 8.3 Finding Discounts

Discount is a reduction given on the Marked Price (MP) of the article.

This is generally given to attract customers to buy goods or to promote sales of the goods. You can find the discount by subtracting its sale price from its marked price. So, Discount = Marked price – Sale price

#### 8.6 Compound Interest

You might have come across statements like “one year interest for FD (fixed deposit) in the bank @ 9% per annum” or ‘Savings account with interest @ 5% per annum

Interest is the extra money paid by institutions like banks or post offices on money deposited (kept) with them. Interest is also paid by people when they borrow money. We already know how to calculate Simple Interest

### NCERT Solutions Class 8 Maths Chapter 8 Comparing Quantities

1. Find the ratio of the following:

(a) Speed of a cycle 15 km per hour to the speed of scooter 30 km per hour.

(b) 5 m to 10 km

(c) 50 paise to ₹ 5

Solution:

a) Ratio of the speed of cycle to the speed of scooter = 15/30 = ½ = 1:2

b) Since, 1 km = 1000m

5m/10km = 5m/(10 x 1000)m = 5/10000 = 1/2000 = 1:2000

The required ratio is 1: 2000

c) Since, ₹1 = 100 paise

50 paise/₹5 = 50/(5 x 100) = 50/500 = 1/10 = 1:10

The required ratio is 1: 10

2. Convert the following ratio to percentages

a) 3:4

b) 2:3

Solution:

a) 3:4 = ¾ = ¾ x 100% = 0.75 x 100% = 75%

b) 2:3 = 2/3 = 2/3 x 100% = 0.666 x 100% = 66.66% = 66⅔%

3. 72% of 25 students are good in mathematics. How many are not good in mathematics?

Solution:

It’s given that 72% of 25 students are good in mathematics

So, the percentage of students who are not good in mathematics = (100 – 72)%

= 28%

Here, number of students who are good in mathematics = 72/100 x 25 = 18

Thus, the number of students who are not good in mathematics = 25 – 18

= 7[Also, 28% of 25 = 28/100 x 25 = 7]

Therefore, 7 students are not good in mathematics.

4. A football team won 10 matches out of the total number of matches they played. If their win percentage was 40, then how many matches did they play in all?

Solution:

Let the total number of matches played by the team be x.

Given that the team won 10 matches and the winning percentage of the team was 40%.

⇒ 40/100 × x = 10

40x = 10 × 100

40x = 1000

x = 1000/40

= 100/4

= 25

Therefore, the team played 25 matches.

5. If Chameli had ₹600 left after spending 75% of her money, how much did she have in the beginning?

Solution:

Let the amount of money that Chameli had, in the beginning, be x

Given that, after spending 75% of ₹x, she was left with ₹600

So, (100 – 75)% of x = ₹600

Or, 25% of x = ₹600

25/100 × x = ₹600

x = 600 × 4

= 2400

Therefore, Chameli had 2400 is the beginning.