Question 40915
given fraction 19/37
required fracion 4/7
numerator = 19+ x
denominator = 37 + x
(19+x)/(37+x) = 4/7
cross multiplying
7*(19+x)=4*(37+x)
expanding
133+7x = 148 + 4x
7x-4x =148-133
3x=15
x=5
verification:
(19+5)/(37+5)=24/42 = 4/7 ..okay!!!
So 5 can be added to obtain the result.