Question

For the first 150 miles of a trip, an car drives at v mph. For the next 200 miles, the car drives at (v

+25) mph. The average speed of the whole trip is 35 mph. Find the value of v.
(A) 20
(B) 25
(C) 30
(D) 35

Answer 1

To find the value of v, we need to use the formula for average speed and set up an equation to solve for v. After solving the equation, v is found to be 20 mph.

Step-by-step explanation:

To find the value of v, we need to use the formula for average speed:

Average speed = Total distance / Total time

Given that the first 150 miles are driven at v mph and the next 200 miles are driven at (v + 25) mph, we can set up the following equation:

35 = (150 + 200) / (150/v + 200/(v + 25))