A pleasure boat on a river traveled from City A to City C with a stop at City B. On the first part of the trip, the boat traveled at an average speed of 10 miles per hour. From City B to City C the average speed was 15 miles per hour. The entire trip covered 150 miles. How long did the entire trip take if the two parts each took the same number of hours?

Question

A pleasure boat on a river traveled from City A to City C with a stop at City B. On the first part of the​ trip, the boat traveled at an average speed of 10 miles per hour. From City B to City C the average speed was 15 miles per hour. The entire trip covered 150 miles. How long did the entire trip take if the two parts each took the same number of​ hours?

GPT 3.5 · Answer

Let's assume that it takes x hours to travel from City A to City B. Since the boat travels at an average speed of 10 miles per hour, the distance from City A to City B is 10x miles.
Similarly, the distance from City B to City C is 15(2x) = 30x miles, as the boat travels at an average speed of 15 miles per hour for 2x hours.
The total distance traveled is 10x + 30x = 40x miles, which is equal to 150 miles.
Therefore, 40x = 150.
Simplifying the equation, we get x = 150/40 = 3.75.
Since it takes x hours to travel from City A to City B, the entire trip takes 3.75 + 3.75 = <<3.75+3.75=7.50>>7.50 hours. Answer: \boxed{7.50}.