SOLUTION: Junior’s boat will go 15 miles per
hour in still water. If he can go 12 miles downstream in the
same amount of time as it takes to go 9 miles upstream,
then what is the speed of
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-> SOLUTION: Junior’s boat will go 15 miles per
hour in still water. If he can go 12 miles downstream in the
same amount of time as it takes to go 9 miles upstream,
then what is the speed of
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Question 173452: Junior’s boat will go 15 miles per
hour in still water. If he can go 12 miles downstream in the
same amount of time as it takes to go 9 miles upstream,
then what is the speed of the current?
Using d=rt I found that 12/15+x = 9/15-x. Then cross multiplied and ended up with 21x=45. x=2.14
Did I work this correctly Answer by solver91311(24713) (Show Source):
The only thing I would do differently would be to leave your answer as a reduced fraction, namely . That is the exact answer, and the answer cannot be represented exactly in decimal form. If your instructor insists on a decimal numerical approximation, I would make the case that the answer is 2 -- that is because you should never express an answer to a calculation involving measurements with greater precision than the least precisely expressed given values. Since both the speed in still water and the distances traveled were expressed as whole numbers, then the answer cannot be expressed with greater precision than rounded to the nearest whole number.
