Examples on Ratios 1

In this class, we discuss Examples on Ratios 1.

The reader should have prior knowledge of ratios basics. Click Here.

Before going to the examples, let’s refresh the concept of the ratio.

Salaries: 1) 1000 2) 10

1000: 10

100: 1

For every 100 Rs of the first person, the second person will have 1 Rupee.

100x: 1x

In place of x, if we place ten, we get the actual salary.

An important point to understand: Ratios are not the actual salaries. Multiply with some x we get actual salaries.

Example 1:

A bag contains 50 paise, 25 paise, and ten paise coins in the ratio 5: 9: 4 amounting to Rs 206.

Find the number of coins of each type.

Solution:

Number of coins are 5x, 9x, and 4x.

5x * 1/2 + 9x * 1/4 + 4x * 1/10 = 206

103x = 4120

x = 40

50 paise coins = 5 * 40 = 200

25 paise coins = 9 * 40 = 360

10 paise coins = 4 * 40 = 160

Example 2:

A mixture contains alcohol and water in a ratio of 4:3.

After adding five liters of water, the ratio changes to 4:5 

Find the quantity of alcohol.

Solution:

Total alcohol and water are 4x and 3x.

After adding five liters of water, the ratio changes to 4:5 

4x/3x+5 = 4/5

20x = 4(3x+5)

8x = 20

x = 2.5

Alcohol = 4 *2.5 = 10 liters.