a tug boat goes 160 miles upstream in 20 hours. return trip takes 5 hours. find the speed of the tu boat without a current, and the speed of the current

Question

a tug boat goes 160 miles upstream in 20 hours.  return trip takes 5 hours. find the speed of the tu boat without a current, and the speed of the current

hero · Answer

@mason2

anonymous · Answer

160/5=32 I got?

anonymous · Answer

I got speed of boat=20, speed, and current 12 ???

hero · Answer

Using the formula d = rt, in this case r = b ± c

b = speed of boat
c = speed of current

Upstream
160 = 20(b - c)

160/20 = b - c
8 = b - c

Downstream 
160 = 5(b + c)
160/5 = b + c
32 = b + c

So we have the two equations:

  8 = b - c
32 = b + c

Add both equations together to get:
40 = 2b
40/2 = b
20 = b

The speed of the boat is 20mph

c = b - 8
c = 20 - 8
c = 12

The speed of the current is 12 mph

hero · Answer

Well, at least you understand the methods

anonymous · Answer

thank you very much!  I did a similar problem, got it right, but I forgot how I did it so thank you.  How do I give you a medal?  I am new here

hero · Answer

Click "Good Answer"

anonymous · Answer

you mean "best response"?