Question

when 40% percent of a number is added to another number the second number increases to its 20%. what is the ratio between the first and second number?

Answer 1

Answer:

1:2

Step-by-step explanation:

Given : when 40% percent of a number is added to another number the second number increases to its 20%.

To Find : what is the ratio between the first and second number?

Solution:

Let x be the first number and y be the another number

We are given that 40% percent of a number is added to another number the second number increases to its 20%.

So, $40\% \times x + y=y+20\% \times y$

$\frac{40}{100}x + y=y+\frac{20}{100}y$

$\frac{40}{100}x =\frac{20}{100}y$

$\frac{x}{y}=\frac{20}{100}\times \frac{100}{40}$

$\frac{x}{y}=\frac{2}{4}$

$\frac{x}{y}=\frac{1}{2}$

Hence the ratio between the first and second number is 1:2