Question

The denominator of a rational number is twice its numerator .if the numerator is decreased by 2 and denominator increased by 4 the no obtained is 3/7 find the rational number

Answer 1

Answer:-

Let the number be x/y.

Given:

The denominator is twice the numerator.

→ y = 2x -- equation (1)

And,

If the numerator is decreased by 2 and denominator is increased by 4 the number obtained is 3/7

→ (x - 2)/(y + 4) = 3/7

On cross multiplication we get,

→ 7(x - 2) = 3(y + 4)

→ 7x - 14 = 3y + 12

Substitute y value from equation (1).

→ 7x - 14 = 3(2x) + 12

→ 7x - 14 = 6x + 12

→ 7x - 6x = 12 + 14

→ x = 26

Substitute x value in equation (1)

→ y = 2(26)

→ y = 52

Hence, the rational number is 26/52 (1/2).