If we have to divide the balloons equally among the children, but we can, not can't, have leftover balloons, we can just divide the total number of balloons, 13, by 3 children.
13/3 = 4 1/3
We have 1 balloon remaining, but that's okay. We gave the maximum number of balloons to each child, which is:
4 balloons, or the answer B.