Answer:
1,152,112.5 cm3
Step-by-step explanation:
To find the volume of this mailbox we can separate in two parts:
A rectangular prism, with dimensions 180 cm x 70 cm x 85.5 cm and
A triangular prism, with dimensions 25 cm x 70 cm x 85.5 cm.
Now we need to find the volume of both parts:
V_rectangular = 180 * 70 * 85.5 = 1,077,300 cm3
V_triangular = (1/2) * 25 * 70 * 85.5 = 74,812.5 cm3
Finally, we just need to sum the volumes of the parts:
V_mailbox = V_rectangular + V_triangular = 1077300 + 74812.5 = 1,152,112.5 cm3
