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exhilaration
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Please re-post this question without the cursor hiding the rate for the bicyclist.
thanks
Andrew
Rate Problem:
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Source: Beat The GMAT — Problem Solving |
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VP_Jim
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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!
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!
Jim S. | GMAT Instructor | Veritas Prep
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exhilaration
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Thanks Jim!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!
Also, sorry it was a bad post but the rate is 20 MPH.
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ghacker
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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 !!!!!!!!!!!!!
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 !!!!!!!!!!!!!
