Answer:
6
Explanation:
I'm only going to answer the first one, then see if you can figure out the others.
We know that 8 students got a B.
We also know that the ratio of students who A's to students who got B's is 3 : 4
The 8 students that got B's is represented by 4 in the ratio.
8 / 4 = 2
Since we can multiply 4 by 2 to get 8, we can do the same to 3 to find out how many students got A's
2 x 3 = 6
6 students got A's