Question

Connie and ron walked to a dock at 2 miles per hour, jumped in a boat and motired to dillons at 7 miles per hour. If the total distance was 14 miles and the trip took 3.25 hours in all, how far did they travel by boat?

Answer 1

10.5 miles

Explanation:

Let b represent the distance traveled by boat. The relation between speed, distance, and time is ...

time = distance / speed

We are told the total time and the total distance so we have ...

b/7 + (14-b)/2 = 3.25

2b +7·14 -7·b = 14·3.25 . . . multiply by 14

3.75·14 = 5b . . . . . . . . . . . .add 5b-14·3.25

b = 10.5 . . . . . . . . . . . . . . . divide by 5

They traveled 10.5 miles by boat.

_____

Check

10.5/7 +3.5/2 = 1.5 +1.75 = 3.25 . . . . the answer checks OK

They spent 1.75 hours walking 3.5 miles to the dock and 1.5 hours traveling 10.5 miles by boat.