Step-by-step explanation:
Area = 8 × 5
Area = 40^2
Perimeter is the length around the edges
Therefore it is 8+8+5×5 (since there are 4 edges)
Perimeter = 2×8 + 2×5
= 40 + 10
= 50cm
2/10 represents 20 percent, as 10 is 100% because it is the Max, so something like 4/10 would be considered 40%
First you would have to multiply 12 times 5 (60) then multiply 7 times 18 (126) you subtract both [ 126 - 60] = (66) that would be your final answer. They both need to have worked 66 minutes to have the same number of boxes.