9514 1404 393
Answer:
1328.4 square units
Step-by-step explanation:
The total surface area is the sum of the areas of the trapezoidal bases, and the areas of each of the four rectangular faces.
The area of each trapezoidal base is ...
A = 1/2(b1 +b2)h
A = 1/2(10 +24)(9) = 153 . . . . square units
__
The total area of the four rectangular faces is ...
A = bh . . . . area of one face
A = 11.4(18) +10(18) +11.4(18) +24(18) = (11.4 +10 +11.4 +24)(18) = 1022.4
So, the total area is ...
SA = 2×base area + face area
= 2×153 +1022.4 = 1328.4 . . . . square units
