By what percent will a fraction change if its numerator is decreased by 10% and its denominator is decreased by 70%?

Answer: it will increase by 200%

Step-by-step explanation:

Lets call the original fraction x/y

and lets call the amount it was increased by a

which means that x/y multiplied by a = 0.9x/0.3y

because the numerator decreased by 10% and the denominator decreased by 70%

because of this you get the equation x/y * a = 0.9x/0.3y

you get xa/y = 0.9x/0.3y

you cross multiply and get the equation 0.3yxa=0.9yx

you cancel the yx from both sides and you're left with 0.3a=0.9

you solve the equation and get a=3

then you make the a percentage which is 300%

you subtract 100% because that is what you began with and get 200%

200 percent increase