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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

2 Answers

6 votes

Final answer:

The speed of the current is found to be 1 mph by setting up an equation based on the times being equal for Maria paddling upstream and downstream, then solving for the current's speed.

Step-by-step explanation:

The question asks us to determine the speed of the current given that Maria can paddle her canoe 2 miles upstream and 6 miles downstream in the same amount of time. She can paddle at a speed of 2 mph in still water. To find the speed of the current, we can use the following approach:

Let the speed of the current be c miles per hour.

When Maria paddles upstream, her effective speed is (2-c) mph.

When she paddles downstream, her effective speed is (2+c) mph.

The time it takes to paddle 2 miles upstream is the distance divided by the effective upstream speed: Time upstream = 2 / (2 - c).

The time it takes to paddle 6 miles downstream is the distance divided by the effective downstream speed: Time downstream = 6 / (2 + c).

Since these times are equal, we have the equation: 2 / (2 - c) = 6 / (2 + c).

Solve for c to find the speed of the current.

Solution Step-by-Step:

1. Write the equation from equal times: 2/(2 - c) = 6/(2 + c).

2. Cross-multiply to clear the denominators: 4 + 2c = 12 - 6c.

3. Collect like terms: 2c + 6c = 12 - 4.

4. Combine like terms: 8c = 8.

5. Solve for c: c = 1 mph.

Therefore, the speed of the current is 1 mph.

User Hamid Asghari
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4 votes
The answer is 2. Imagine Maria can paddle 4 miles in either direction if there was no current in 2 hours. But if we add the current then we would subtract 2 when she goes upstream so she would get 4-2 which is 2 miles. And would get an extra 2 miles going downstream. So 4+2= 6 miles.

So the speed of the current is 2 mph.

Hope this helps!
User Avolquez
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5.1k points