Question

a fraction becomes 4/5 if is added to both numerator or and denominator if however is subtracted from both numerator and denominator the fraction becomes 1/2 what is the fraction​

Answer 1

ANSWER

Let the fraction be yx

⇒y+1x+1=54

⇒5x+5=4y+4⇒5x−4y=−1....(1)

⇒y−5x−5=21

⇒2x−10=y−5⇒2x−y=5.....(2)

⇒y=2x−5

substitute the value of y in equation (1)

⇒5x−4(2x−5)=−1

⇒5x+20−8x=−1⇒x=7

Put the value of x   in   eqn (2)

⇒y=2×7−y=5⇒y=9

∴yx=97