SOLUTION: A jet ski with average speed of 60 mph left a pier by the river upstream. Fifteen minutes after its motor broke, and it began drifting downstream for 3 hours and 45 minutes until r

Algebra.Com
Question 1133091: A jet ski with average speed of 60 mph left a pier by the river upstream. Fifteen minutes after its motor broke, and it began drifting downstream for 3 hours and 45 minutes until reached another pier, which was 2 miles away down the river from the original pier. What is the rate of the current, in mph?
Answer by ikleyn(52810)   (Show Source): You can put this solution on YOUR website!
.
Let the rate of the current be "x" miles per hour.

Then the speed of the jet ski upstream is (60-x) mph.


Moving   of an hour upstream, it covered the distance    miles.


Then it moved downstream with the speed equal to the rate of the current x mph during   hours =  hours 

and covered the distance   downstream.


We are given that  


     =  + 2.


It is your basic equation.

To solve it, multiply first both sides by 4; then simplify step by step:


    15x = 60-x + 8

    15x + x = 60 + 8

    16x = 68  ==============>  x =  = .


ANSWER.  The rate of the current is   =  miles per hour.


RELATED QUESTIONS

A motorboat, moving at a speed of 10 km/hour, left a pier traveling against the current... (answered by josgarithmetic)
the river current is 8 mph. a jet ski can travel 34 miles downstream in the same time... (answered by Alan3354)
the river current is 8 mph. a jet ski can travel 34 miles downstream in the same time... (answered by josgarithmetic)
A Jet Ski rider can travel 16 miles against the current of the lower Mississippi River in (answered by oberobic)
Byron wanted to try out different water craft. He went 124 miles downstream in a motor... (answered by Theo)
A jet ski has an initial value of $9800. The jet ski depreciates by 12% per year after it (answered by jorel555)
Joshua drives a jet ski on a sunny day 100 km away. The current speed of the water is 50... (answered by stanbon)
Question 400689: A sight seeing boat travels an average speed of 22 mph in the calm water (answered by josgarithmetic)
a motor boat goes 5 miles upstream in the same time it requires to go 7 miles downstream. (answered by mananth)