Answer:
408
Step-by-step explanation:
Surface area formula is A=2(wl+hl+hw)
Substituting these values into the formula you would get
2·(3·8+4·8+4·3)=136
136 accounts for one rectangular prism.
Since you have 3 multiply 136 by 3 which would leave you with 408
Answer:
280 in²
Step-by-step explanation:
The opposite faces are congruent , then surface area (SA ) is
SA = top/ base + front/ back + 2 sides
note for the front/ back and 2 sides we have 3 + 3 + 3 = 9 in
SA = 2(8 × 4) + 2(8 × 9) + 2(4 × 9)
= 2 × 32 + 2 × 72 + 2 × 36
= 64 + 144 + 72
= 280 in²
