Mousy=m
Mrs. Computer=3m
m+3m=52
4m=52
m=52/4
m=13
mousy=13, Mrs. Computer=3*13=39
The answer would be (2,3).
Try sketching it out, it helps :)
The dimensions of the carton are:
10 x 10 x 10 [inch OR unit cubes - it's the same since cubes' dimensions are 1 x 1 x 1 inch)
I attach the explanation below.