Question

25. The sum of 1/5th of the number and 25% of another number is equal to 40% of the first number. What is the ratio of the first number and the second number?
4:3
5:2
5:4
6:5​

Answer 1

Answer:

5 : 4

Step-by-step explanation:

Let the first number be x and second number be y.

Sum of 1/5th of the number and 25% of another number is equal to 40% of the first number.

=> (1/5) of x + 25% of y = 40% of x

=> (1/5 × x) + (25/100 × y) = (40/100 × x)

=> (x/5) + (y/4) = (2x/5)

=> y/4 = (2x/5) - (x/5)

=> y/4 = (2x - x)/5

=> y/4 = x/5

=> 5/4 = x/y

Ratio of the numbers is 5:4

Answer 2

Given :-

Sum of 1/5  of the number and 25% of another number is equal to 40% of the first number.

To Find :-

Ratio of 1st and 2nd number

Solution :-

Let the number be a and b

$\sf\dfrac{1}{5} \times a + 25\% \times b = 40\% \; of \; a$

1/5  × a + 25/100  × b = 40/100  × a

1/5  × a + 5/20 × b =4/10  × a

a/5 + 1/4 × b = 2/5 × a

a/5 + b/4 = 2a/5

b/4 = 2a/5 - a/5

b/4 = 2a - a/5

b/4 = a/5

a/b = 5/4