You are making poster board boundary markers in the shape of square pyramids for a relay race. If you are including a 10-inch square as the bottom and you want the slant height to be 12inches, how much poster board do you need?

Question

You are making poster board boundary markers in the shape of square pyramids for a relay race. If you are including a  10-inch square as the bottom and you want the slant height to be 12inches, how much poster board do you need?

anonymous · Answer

340in.2
360in.2
400in.2
384in.2

anonymous · Answer

@karatechopper , @annas , @seashell  anyone help plzz

anonymous · Answer

There are 4 triangular sides (one for each side of the square), so we multiply the area of ONE triangle by 4
112 in2 × 4 = 448 in2
Total surface area is 196 in2 + 448 in2 = 644 in2
--->644 in2

anonymous · Answer

it cant be 644

anonymous · Answer

the 2 i put after in. is small like this|dw:1339542914544:dw|

anonymous · Answer

@seashell plz answer me

anonymous · Answer

are you still here

anonymous · Answer

sorry i wasnt on

anonymous · Answer

can you help me now

anonymous · Answer

yeah :) hold on... im rechecking :)

anonymous · Answer

you have 1 square, area 100. Then each triangle has area (0.5 x 10 x 12)=60, and there are four. so 100 + 4(60)= 100+240 = 340

anonymous · Answer

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