Question

ONLY FBI CAN ANSWER THIS: By what percent will a fraction change if its numerator is decreased by 10% and its denominator is decreased by 70%?

Answer 1

The correct answer is that the new fraction will be three times bigger than the original fraction (300%).

Explanation:

Let's prove the answer with five examples, this way:

1/2 ⇒ ( 1 - 10%)/(2 - 70%) = 0.9/0.6 = 1.5 = 3/2, that is 3 times 1/2

1/8 ⇒ ( 1 - 10%)/(8 - 70%) = 0.9/2.4 = 0.375 = 3/8, that is 3 times 1/8

11/17 ⇒ ( 11 - 10%)/(17 - 70%) = 9.9/5.1 = 1.9412 = 33/17, that is 3 times 11/17

π/10 ⇒ ( π - 10%)/(10 - 70%) = 2.8274/3 = 0.94248 = 3π/10, that is 3 times π/10

5/6 ⇒ ( 5 - 10%)/(6 - 70%) = 4.5/1.8 = 2.5 = 5/2, that is 3 times 5/6

The FBI answered that the new fraction will be three times bigger than the original fraction (300%).