+0  
 
0
407
3
avatar

A boat on a river travels 20 miles downstream in only 2 hours. It takes the same boat 6 hours to travel 12 miles upstream. What are the speed of the boat and speed of the current?

math
Guest Aug 24, 2014

Best Answer 

 #1
avatar+90988 
+10

When traveling downstream speed = boat + current = 20miles in 2 hours = 10miles/hour

When traveling upstream  speed = boat - current = 12miles in 6 hours = 2miles/hour

 

so we have 2 equations which must be solved simultaneously.

B+C=10

B-C=2

add and we get

2B=12

B=6

subtract and we get

2C=8

c=4

So the boat is traveling at 6 miles per hour and the current is traveling at 4 miles/hour.

Melody  Aug 24, 2014
Sort: 

3+0 Answers

 #1
avatar+90988 
+10
Best Answer

When traveling downstream speed = boat + current = 20miles in 2 hours = 10miles/hour

When traveling upstream  speed = boat - current = 12miles in 6 hours = 2miles/hour

 

so we have 2 equations which must be solved simultaneously.

B+C=10

B-C=2

add and we get

2B=12

B=6

subtract and we get

2C=8

c=4

So the boat is traveling at 6 miles per hour and the current is traveling at 4 miles/hour.

Melody  Aug 24, 2014
 #2
avatar+78577 
0

Very nice, Melody.......

 

CPhill  Aug 24, 2014
 #3
avatar+90988 
0

Thank you Chris,

I really liked this little question.

I've asked Ninja to include it in he sample questions.  

Melody  Aug 25, 2014

9 Online Users

avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details