Problem Solving

I am learning to draw a picture to help me solve a problem.

The problem that I had to solve was:

Larenzo has 3 times as many marbles than Janet does. Janet has 7 marbles. How many marbles does Larenzo have?

Miss Hughes came and did some problem solving with us. I drew the problem. I put three boxes and then put seven dots in the boxes for marbles. Then we added them altogether and I got 21.