Need , i know the basic math. how do i solve this?

(7/15)/(3/5)
easy
(a/b)/(c/d)=(a/b)(d/c)
invert and multiply (what it does is it cancels the bottom and makes it one)
(7/15)/(3/5)=(7/15)(5/3)=35/45=7/9

answer is C

Easy the answer is c 7/9 . First I did the dividing of 7/15 and 3/5 whenever u do this our teacher told us to do same change flip. 7/15 by 3/5 equals 7/15 times 5/3 which u would then multiply straight across and get 35/45 which when divided is simplified to 7/9. I hope this helped u!