Rate Problem:

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Rate Problem:

by exhilaration » Sat May 30, 2009 6:08 pm
Hi, can anyone please solve the question below.

Thanks.
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by mbadrew » Sat May 30, 2009 6:12 pm
Please re-post this question without the cursor hiding the rate for the bicyclist.

thanks
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by VP_Jim » Sat May 30, 2009 6:46 pm
The cyclist is going 20 mph.

So, to solve, you need to determine how far each (the hiker and the cyclist) will go in 5 minutes.

The hiker is going 4 miles per hour. To convert to "miles per 5 minutes" we want to divide 4/12 = 1/3. So, the hiker will go 1/3 of a mile in 5 minutes.

The cyclist is going 20 miles per hour. Again, divide that by 12 to get miles per 5 minutes = 5/3.

So, when the cyclist passes the hiker, they are in the exact same spot. Five minutes later, the cyclist has gone 5/3 miles and the hiker has gone 1/3 of a mile. Therefore, the hiker is now 5/3 - 1/3 = 4/3 miles behind.

The hiker needs to go 4/3 miles to catch up, which will take him 20 minutes moving at the rate of 1/3 miles per 5 minutes.

Hope this helps!
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by exhilaration » Sat May 30, 2009 8:19 pm
VP_Jim wrote:The cyclist is going 20 mph.

So, to solve, you need to determine how far each (the hiker and the cyclist) will go in 5 minutes.

The hiker is going 4 miles per hour. To convert to "miles per 5 minutes" we want to divide 4/12 = 1/3. So, the hiker will go 1/3 of a mile in 5 minutes.

The cyclist is going 20 miles per hour. Again, divide that by 12 to get miles per 5 minutes = 5/3.

So, when the cyclist passes the hiker, they are in the exact same spot. Five minutes later, the cyclist has gone 5/3 miles and the hiker has gone 1/3 of a mile. Therefore, the hiker is now 5/3 - 1/3 = 4/3 miles behind.

The hiker needs to go 4/3 miles to catch up, which will take him 20 minutes moving at the rate of 1/3 miles per 5 minutes.

Hope this helps!
Thanks Jim!

Also, sorry it was a bad post but the rate is 20 MPH.

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by ghacker » Wed Jun 10, 2009 9:14 am
If you read the question carefully you see that the speeds are proportional

That is the hikers speed is 1/5 th of that the cyclist

This means that if the hiker moves X miles in one minute the cyclist will move 5X miles

So the actually the cyclist has only moved 20X miles in 5 min relative to the hiker so the hiker will take 20x/ x minutes

so the answer is 20 min

We need not convert !!!!!!!!!!!!!