- - Let's solve for C.
Starting off with our equation:

Transform:

Solve for that:

Solve for that for the last time and your answer is
The legnth is irrelivant
we know that
Circumference=2 times pi time radius
c=40
40=2 times pi times radius
divide both sides by 2
20=pi times radius
divide both sides b pi
20/pi=radius
the radius is 20/pi cm or aproximately 6.366199048 cm
Answer:
240 miles
Step-by-step explanation:
Step 1
We find the constant rate at which the family travels
Speed(Rate) = Distance/Time
A Family travels at a constant rate and drove 420 miles in 7 hours.
Speed(Rate) = 420 miles/7 hours
= 60 miles per hour
Step 2
If they drive at the same speed ,How many miles will they drive in the next four hours.?
We are to finally calculate the distance for the next 4 hours
Distance = Speed × Time
Speed = 60 miles per hour
Time = 4 hours
Distance = 60 miles per hour × 4 hours
Distance = 240 miles
Therefore, for the next 4 hours the number of miles they would drive is 240 miles