Maria can paddle her canoe 2 miles upstream against the current in the same time it would take her to paddle 6 miles downstream. Maria can paddle 2 mph in still water. What is the speed of the current?

Respuesta :

Answer:

Step-by-step explanation:

Maria can paddle her canoe 2 miles upstream against the current in the same time it would take her to paddle 6 miles downstream.

Maria can paddle 2mph in still water.

What is the speed of the current?

:

let c = the rate of the current

then

(2-c) = effective speed upstream

and

(2+c) = effective speed downstream

:

Write a time equation; time = dist/speed

Two mi upstr time = six mi downstr time

2%2F%28%282-c%29%29 = 6%2F%28%282%2Bc%29%29

Cross multiply

2(2+c) = 6(2-c)

4 + 2c = 12 - 6c

2c + 6c = 12 - 4

8c = 8

c = 1 mph is the current

:

:

Check this, find the time each way,

effective speed down: 2 + 1 = 3 mph

effective speed up: 2 - 1 = 1 mph

6/3 = 2 hr

2/1 = 2 hrs