Jack's father drives to work in 30 minutes when driving at his usual speed. When traffic is bad, he drives 30 miles per hour slower and the trip takes one hour longer. How far is Jack's fathers work from home.

22.5 miles

Step-by-step explanation:

No traffic :

Let speed = x

Time taken = 30 = 30/60 = 0.5 hour

Speed = distance / time

Distance = d

x = d / 0.5 - - - (1)

With traffic :

Speed = x - 30

Time taken = 1 hour 30 minutes = 1.5 hour

x - 30 = d / 1.5

x = d/1.5 + 30 - - - - (2)

Equating (1) and (2)

d / 0.5 = d/1.5 + 30

d /0.5 - d /1.5 = 30

(1.5d - 0.5d) / 0.75 = 30

1.5d - 0.5d = 22.5

1d = 22.5

Hence,

d = 22.5 miles

answer: the answer is (b) amie should have multiplied

step-by-step explanation: given a sphere and a cylinder with same radius and height.

let, 'r' be the radius of the cylinder and sphere and 'h' be the height of the cylinder. according to the question,

r = h.

now, the volume of the sphere will be

and the volume of the cylinder will be

therefore, we have

thus, ammie should have multiplied the volume of the sphere