Question

A pile of earth removed from an excavation is a cone measuring 12 ft high and 30 ft across its base. How many trips will it take to haul away the
earth using a dump truck with a capacity of 9 cubic yards?


trips =

Answer 1

Answer:

12 trips

Step-by-step explanation:

Given;

Dimension of cone shapef pile of earth;

height h = 12 ft = 4 yards

diameter d = 30 ft = 10 yards

radius r = d/2 = 10/2 = 5 yards

The volume of a cone V;

V = (1/3)πr^2 h

Substituting the given values;

V = (1/3) ×π × 5^2 × 4 cubic yards

V = 104.72 cubic yards

Given that a dump truck have a capacity of 9 cubic yards.

Vc = 9 cubic yards

Number of trips it will take is;

N = Volume of earth pile/truck capacity

N = V/Vc

Substituting the values;

N = 104.72/9

N = 11.64

N ≈ 12 trips

Therefore, the truck will make 12 trips