power prep 2 and hikers
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- Brent@GMATPrepNow
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With this question, it helps to refrain from performing more calculations than are necessary.
The important thing is to recognize that if someone is travelling 5 times faster than me, it will take me 5 times longer to get to the same destination as the person travelling faster.
So, if it takes the cyclist 5 minutes to travel a certain distance, it will take the hiker 5 times as long to travel the same distance.
So, the hiker will take 25 minutes - Answer choice D
The important thing is to recognize that if someone is travelling 5 times faster than me, it will take me 5 times longer to get to the same destination as the person travelling faster.
So, if it takes the cyclist 5 minutes to travel a certain distance, it will take the hiker 5 times as long to travel the same distance.
So, the hiker will take 25 minutes - Answer choice D
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Hiker- 4m/h
cyclist 20 m /h
from the point where they meet cyclist travelled for 5 min further
so in 5 min
20 --- 60
x------5
60x=100
x=10/6 miles
jiker to cover the distance of
4---- 60
10/6---y
4y=100
y =25 min
Vishu
cyclist 20 m /h
from the point where they meet cyclist travelled for 5 min further
so in 5 min
20 --- 60
x------5
60x=100
x=10/6 miles
jiker to cover the distance of
4---- 60
10/6---y
4y=100
y =25 min
Vishu
KILL !! DIE !! or BEAT my FEAR !!! de@D END!!
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Forgot to consider ! the five mintues hiker covered whilst cyclist for 5 min
Hiker distance after 5 minutes
r = 4 miles / 1 hour -> 4 miles / 60 minutes -> 1 mile / 15 minutes
t = 5 minutes
d = r*t -> 1/15 * 5 = 1/3 miles
Cyclist distance after 5 minutes
r = 20 miles / 1 hour -> 20 miles / 60 minutes -> 1 mile / 3 minutes
t = 5 minutes
d = r*t -> 1/3 * 5 = 5/3 miles
Distance between the two after 5 minutes
5/3 - 1/3 = 4/3 miles
Time it takes Hiker to travel 4/3 miles
4/3 = 1/15 * t
t = 20 minutes
Hiker distance after 5 minutes
r = 4 miles / 1 hour -> 4 miles / 60 minutes -> 1 mile / 15 minutes
t = 5 minutes
d = r*t -> 1/15 * 5 = 1/3 miles
Cyclist distance after 5 minutes
r = 20 miles / 1 hour -> 20 miles / 60 minutes -> 1 mile / 3 minutes
t = 5 minutes
d = r*t -> 1/3 * 5 = 5/3 miles
Distance between the two after 5 minutes
5/3 - 1/3 = 4/3 miles
Time it takes Hiker to travel 4/3 miles
4/3 = 1/15 * t
t = 20 minutes
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- logitech
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4.......>
20.......>
So actually for 5 minutes the distance will be: 5(20-4)
time = (5x16) / 4
time = 20 minutes
20.......>
So actually for 5 minutes the distance will be: 5(20-4)
time = (5x16) / 4
time = 20 minutes
LGTCH
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- ronniecoleman
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Relative speeds come into picture:
V1 == Hiker
V2 == Cyclist
For 5 mins ( 1/12 hours)
Distance between them would be 20-4/1/12
= 4/3
Now to cover 4/3 miles
Hiker will take (4/3)/4
that is 1/3 hours
that is 20 minutes:
V1 == Hiker
V2 == Cyclist
For 5 mins ( 1/12 hours)
Distance between them would be 20-4/1/12
= 4/3
Now to cover 4/3 miles
Hiker will take (4/3)/4
that is 1/3 hours
that is 20 minutes:
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Amen to thatBrent Hanneson wrote:With this question, it helps to refrain from performing more calculations than are necessary.
The important thing is to recognize that if someone is travelling 5 times faster than me, it will take me 5 times longer to get to the same destination as the person travelling faster.
So, if it takes the cyclist 5 minutes to travel a certain distance, it will take the hiker 5 times as long to travel the same distance.
So, the hiker will take 25 minutes - Answer choice D
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