Surface area (super easy 8th grade math)

Question

a box is 5ft long 4ft wide and 3ft high is being gift wrapped. if wrapping costs 5 cents per square foot, how much does it cost to wrap the box?

Answer 1

2(5x4 + 5x3 + 4x3) = 2(20+15+12) = 2(47) = 94

.05 x 94 = $4.70 to wrap the box

There are 6 sides. 2 sides are 5x4=20 for 40 ft^2

2 sides are 5x3 =15, for 30 ft^2

2 sides are 3x4 = 12 for 24 ft^2

40+30+24 = 94 ft^2

94 times 5 cents = 470 cents = $4.70 total cost