Question

a bathtub is in the shape of a rectangular prism. its dimensions are 5 feet by 3 feet by 18 inches. the bathtub is three-fourths full of water and drains at a rate of 1 cubic foot per minute. about how long does it take for all the water to drain?

Answer 1

To solve for the time it takes to drain the water, we must first solve the total volume of the bath tub. Since it is a rectangular prism, therefore the formula for volume is:

V = l * w * h

where,

l , w and h are the dimensions of the prism

l = 5 ft

w = 3 ft

h = 18 inches = 1.5 ft

 

Substituting the given values:

V = (5 ft) (3 ft) (1.5 ft)

V = 22.5 cubic foot

 

Since the bath tub is only 3/4 full of water, therefore the volume of water is:

V water = (3/4) V

V water = (3/4) (22.5 cubic foot)

V water = 16.875 cubic foot

 

Since the rate is 1 cubic foot per minute therefore the time required is:

time = volume / rate

time = 16.875 cubic foot / (1 cubic foot / minute)

time = 16.875 minutes = 16.9 minutes