Question

A boat has a speed of 15 mph in still water. It travels downstream from Greentown to Glenavon in g hours. It then goes back upstream from Glenavon to Cambria, which is 2 miles downstream from Greentown, in g hours. Find the rate of the current.

Answer 1

Step-by-step explanation:

We want to find two things-- the speed of the boat in still water and the speed of the current.  Each of these things will be represented by a different variable:

B = speed of the boat in still water  

C = speed of the current

Since we have two variables, we will need to find a system of two equations to solve.

How do we find the two equations we need?  

Rate problems are based on the relationship Distance = (Rate)(Time).

Fill in the chart with your data (chart attached)

The resulting speed of the boat (traveling upstream) is B-C miles per hour.  On the other hand, if the boat is traveling downstream, the current will be pushing the boat faster, and the boat's speed will increase by C miles per hour.  The resulting speed of the boat (traveling downstream) is B+C miles per hour.  Put this info in the second column in the chart.  Now plug it into a formula! Distance=(Rate)(Time) Now solve using the systems of equations!