Answer:
77.14 minutes.
Step-by-step explanation:
Jack's time = 3 hours
Jill's time = 2.25 hours = 2 1/4 = 9/4 hours
Combined time = x
Rates :
Jack = 1/3 ; jill = 1 / 2.25 = 1 / 9/4 = 4 /9
Combined rate = 1/x
Setting up the equation :
1/3 + 4/9 = 1/x
Lcm of 3 and 9 = 9
(3 + 4) / 9 = 1/x
7/9 = 1/x
Cross multiply :
7x = 9
x = 9/7 hours
x = (9/7)* 60
x = 77.14 minutes
Combined time = 77.14 minutes.
Answer:
The cubic volume of concrete needed to complete the ramp is 360 ft³
Step-by-step explanation:
We note that the ramp shape is that of a right ngled triangular cube with dimensions
Height = 10 ft
Base = 12 ft
Width = 6 ft
The amount of concrete to fill the ramp is approximately the volume of the ramp.
Volume of ramp = volume of triangular prism = 0.5×Base ×Height × Width
Volume of ramp = 0.5×12×10×6 = 360 ft³.
The cubic volume of concrete needed to complete the ramp = 360 ft³.
The answer should be 5 egg cartons
Answer:
what form is the question?