SOLUTION: Please help me!! I get so confused with these. 4.Follow the 5 steps below to complete this problem. (4 points) Step 1: Pick a friend or family member to be the character

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Question 926420: Please help me!! I get so confused with these.

4.Follow the 5 steps below to complete this problem. (4 points)
Step 1:
Pick a friend or family member to be the character of your word problem. This friend or family member may do one of the following:
•Drive a boat
•Drive a jet ski
Step 2:
Select a current speed of the water in mph.
Step 3:
Select the number of hours (be reasonable please) that your friend or family member drove the boat or jets ski against the current speed you chose in step 2.
Step 4:
Select the number of hours that your friend or family member made the same trip with the current (this should be a smaller number, as your friend or family member will be traveling with the current).
Step 5:
Write out the word problem you created and calculate how fast your friend or family member was traveling in still water. Round your answer to the nearest mph.

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

My friend Ken will drive a boat.

Step 2:
Select a current speed of the water in mph.
Speed of current will be 7mph.

Step 3:
Select the number of hours (be reasonable please) that your friend or family member drove the boat or jets ski against the current speed you chose in step 2.
Ken will drive the boat upstream 60 miles in 6 hours.

Step 4:
Select the number of hours that your friend or family member made the same trip with the current (this should be a smaller number, as your friend or family member will be traveling with the current).
Ken will drive the boat downstream 72 miles in 3 hours.

Step 5:
Write out the word problem you created and calculate how fast your friend or family member was traveling in still water. Round your answer to the nearest mph.

Ken wanted to try out his new boat so he parked his car and a friend drove him to the marina where he took possession of his boat. He drove the boat upstream 60 miles for 6 hours and then back downstream 72 miles (to where his car with boat carrier was parked) in 3 hours. What was the speed of the boat in still water?

Solution:
Let C mph equal the Current of the river and b mph the rate of the boat.
Remember that d+=+st (distance = speed * time)
Upstream:
60+=+6%28b-c%29
Downstream: 72+=+3%28b%2Bc%29
So we have two equations:
60+=+6b+-+6c
72+=+3b+%2B+3c
_______________________
Solve both equations for b:
b+=+10+%2B+c
b+=+24+-+c
_________________________
Now set equal to each other and solve for c:
10+%2B+c+=+24+-+c
2c+=+14
c+=+7mph
So the speed of the current was 7mph
Now plug this into either of the original equations to find the speed of the boat in still water.
We will choose the first one:
b+=+10+%2B+c
b+=+10+%2B+7
b+=+17
The speed of the boat in still water was 17mph.