Kendra found the surface area of the prism below. She started by finding the surface area of the triangle and did 16*12 to get 192. Then she multiplied that by 2 and got 384.
Next she found the areas of the rectangles by doing 10*20 = 200, 12*10 = 120, and 16*10 = 160.
Finally, she added all the area together and got 672cm squared.
Where did Kendra make her mistake?
