Answer:
32 black grapes
Explanation:
3:4 is the same as 3/4 so we Know that the ratio is green to black.
There are 24 grapes which means the ratio is 24:? Now you ask yourself what is 24 3/4s of .... 32
24/32 and to check simplify
24/8
32/8
3/4 therefore this is the correct answer
(hope this helps, sorry if I didn't explain well)