Answer:
519.2 in²
Explanation:
First find the slant height (s) of the triangle that makes up 1 side of the pyramid:
s² = 18² + (24/2)² = 468
s= √468 = 21.63
Now find the area of one side of the pyramid:
A = 1/2bh = 1/2(24)(21.63) = 519.2 / 2 = 259.56
Total area (all 4 sides) of the pyramid = 4(259.56) = 1038.2
1/2 the surface area is yellow:
1038.2 / 2 = 519.2 in²