A 12-ft-by-15-ft rectangular swimming pool has a 3-ft-wide no-slip surface around it. What is the outer perimeter of the no-slip surface?

A. 78 ft
B. 78 ft^2
C. 198 ft
D. 198 ft^2

Question

A 12-ft-by-15-ft rectangular swimming pool has a 3-ft-wide no-slip surface around it. What is the outer perimeter of the no-slip surface?

A. 78 ft
B. 78 ft^2
C. 198 ft
D. 198 ft^2

anonymous · Answer

You have to first add 3 to the legth and Width, what do you get?

excalibur0126 · Answer

Would it be 15-ft-by-18-ft or 18-ft-by-21-ft?

anonymous · Answer

it would be 15 by 18

anonymous · Answer

then you have to add 3 more because of the other side, so 18 by 21

excalibur0126 · Answer

That makes sense, thanks for the quick reply :)

anonymous · Answer

No problem! Good luck with your math

anonymous · Answer

A.
$$2 ((12+6)+(15+6))=78 $$

anonymous · Answer

78 is the no-slip surface perimeter as requested in the problem statement.