3/7 x 28/9 x 15/17 how do i use cancellation? my answer was 15/17 but thats not the right answer, can someone explain this and cancelling factors to

Question and answers are in the attached picture. you so much in advance.

Acolony contains 1500 bacteria. the population increases at a rate of 115% each hour. if x represents the number of hours elapsed, which function represents the scenario? f(x) = 1500(1.15)" f(x) = 1500(115) f(x) = 1500(2.15) f(x) = 1500(215)

Using inductive reasoning, what are the next two number in this set? 2,3/2,4/3,5/4,