Question

Divide 33 photos into 2 groups so the ratio is 4 to 7.

Answer 1

so you want two groups that are in a ratio of 4 to 7
so 33=4x+7x
so 33=11x
so x=3

that means the groups are 4*3= 12 and 7*3=21

Answer 2

Let, 
the number of phots be "4x" and "7x".
Now,
According to the question,
4x + 7x = 33
11x = 33 / 11
x = 3

Now,
 4x = 4(3) = 12

7x = 7(3) = 21

So, there are 12 photos in one group and 21 photos in the another group