Question

With the aid of the current Andrew can tow a canoe 4 miles in 16 minutes, against the current it takes him 20 minutes the same distance, how fast does Andrew go in still water? How fast is the current?

Answer 1

0.225miles per minute for boat and 0.025 miles per minute for current

Explanation:

you just gotta love river current problems

lets use the formula d=rt

we're gonna modify it a bit

when your riding in a canoe with the current your going to go faster than against the current so

with the current: d=(r+c)t

against current:d=(r-c)t

where

d=distance

c=rate of water

r=rate of boat

and

t= time

so

4=16(r+c)

4=16r+16c

simplify to

1=4r+4c

2nd equation:

4=20(r-c)

4=20r-20c

solve by elimination:

(1=4r+4c)5

5=20r+20c

-

4=20r-20c

-------------------

1=40c

c=0.025-speed of water

4=20r-20(0.025)

4=20r-0.5

4.5=20r

4.5/20=r

0.225=rate of boat

hope this helps