Question

A fraction becomes 4 when 1 is added to both the numerator and denominator and it becomes 7 when 1 is subtracted from both the numerator and denominator.The numerator of the given fraction is [1](a) 2 (b) 3(c) 5 (d) 15

Answer 1

Answer:

Correct Answer:

D) 15

Description for Correct answer:

Let the fraction be xy

Therefore, x+1y+1=4 ...(1)

Therefore, x+1=4(y+1)

x−1y−1=7 ...(2)

x−1=7(y−1)

Therefore, x−7y=6 ...(4)

x−4y=3 ...(3)

x−7y=−6 ...(4)

solving, subtracting 3y=9, y=3

put the value of y in (3), we get x−12=3, x=15

Therefore, The numerator of the given fraction is 15.

Answer 2

hi mate

here is

your answer is starts a fraction becomes 4 when 1 is added to both the numerator and denominator and it becomes 7 when 1 is subtracted from both the numerator and denominator. mated you find the numerator of the given fraction is. so mate therefore, The numerator of the given fraction is 15.

solution

Let the fraction be

y/x

so mate...

then according to the question,

y+1/x+1 =4 .....(1) and

y−1/x−1 =7 .....(2)

From (1),

x+1=4(y+1)

x=4y+3 ....(3)

From (2),

x−1=7(y−1)

x=7y−6 ....(4)

From (3) and (4),

4y+3=7y−6

3y=9

y=3 ...(5)

From (4) and (5),

x=4×3+3=15

Numerator of the fraction =x=15

i hope mate it helpfull to you...