Answers:
the first rectangular prism is 75 in.
the second rectangular prism is 55.125 inches
Explanation:
L=Length
W=Width
H=Height
Prism 1:
L=7 1/2= 7.5
W=4
H=2 1/2= 2.5
7.5 x 2.5 x 4
7.5 x 2.5 = 18.75
18.75 x 4 = 75
Rearranging to check my work:
7.5 x 4 x 2.5
7.5 x 4 = 30
30 x 2.5 = 75
I was right.
For prism 2:
L=5 1/4 = 5.25
W=3 1/2 = 3.5=3.50
H=3
5.25 x 3.50 x 3
5.25 x 3.50 = 18.37500 = 18.375
18.375 x 3 = 55.12500 = 55.125
Rearranging to check my work:
3 x 5.25 x 3.50
3 x 5.25 = 15.75
15.75 x 3.50 = 55.12500 = 55.125
I was right.
Hope this answers your question.