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Percentage

by hai1 » Mon Mar 08, 2010 5:55 am
If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j ?


a 0.35 b 3.5 c. 35 d. 350 e. 3500

My approach:
1.25J=0.25K => K=5J
1.5K=0.5l => l=3K
0.75m=1.75l => m=(7/3)l

0.2m=2j*x; X=?

2j*x= 0.2m
2j*x= 0.2*(7/3)l
2j*x= 0.2*(7/3)*3k
2j*x= 0.2*7*5j
x=.1*7
%x=70%

Where am I going wrong?

OA: D
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by dtweah » Mon Mar 08, 2010 6:40 am
hai1 wrote:If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j ?


a 0.35 b 3.5 c. 35 d. 350 e. 3500

My approach:
1.25J=0.25K => K=5J
1.5K=0.5l => l=3K
0.75m=1.75l => m=(7/3)l

0.2m=2j*x; X=?

2j*x= 0.2m
2j*x= 0.2*(7/3)l
2j*x= 0.2*(7/3)*3k
2j*x= 0.2*7*5j
x=.1*7
%x=70%

Where am I going wrong?

OA: D
You went wrong from .2m x =2j *x :

You should have had .2m = x% 2j

This gives

X= 10M/J

We know L= 3M/7 so 3m/7= 3K or K= m/7

K = 5J

m/7 = 5J

J= m/35

X= 10m/m/35 or 10m x 35/m = 350
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by thephoenix » Mon Mar 08, 2010 7:24 pm
hai1 wrote:If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j ?


a 0.35 b 3.5 c. 35 d. 350 e. 3500

My approach:
1.25J=0.25K => K=5J
1.5K=0.5l => l=3K
0.75m=1.75l => m=(7/3)l

0.2m=2j*x; X=?

2j*x= 0.2m
2j*x= 0.2*(7/3)l
2j*x= 0.2*(7/3)*3k
2j*x= 0.2*7*5j------->x=7/2=3.5=350%
x=.1*7------->cal mistake
%x=70%
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by thebigkats » Mon Feb 07, 2011 3:12 pm
this is a great example for Pick The Value type question:

If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j

Lets say J = 100
25% K = 125% of 100
==> K = 125 * 100/25 = 500
150% of K = 50% L
==> 750 = 50%L
==> L = 1500
175% L = 75% M
==> 1.75 * 1500 = 75% M
==> M = 1500 * 1.75 * 100 / 75
==> M = 3500
20% M = 700
200% J = 200

Answer = (700 / 200) * 100 = 350%
Hence D
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by Night reader » Mon Feb 07, 2011 3:44 pm
all percentage is translated into decimals - multiply the answer by 100
5j/4=k/4 <> 5j=k
3k/2=l/2 <> 3k=l
7l/4=3m/4 <> 7l=3m ..................................................75%=3/4;175%=1 3/4
find x from `` m/5=x*2j <> m=x*10j

10j=2k --> 2k=2l/3 --> 2l/3=3m/7 *2/3=2m/7 Thus 10j=2m/7 substitute into m=x*10j --> m=x*2m/7 --> x=7m/2m, x=3.5
3.5*100=350% (answer D) :)
hai1 wrote:If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j ?


a 0.35 b 3.5 c. 35 d. 350 e. 3500

My approach:
1.25J=0.25K => K=5J
1.5K=0.5l => l=3K
0.75m=1.75l => m=(7/3)l

0.2m=2j*x; X=?

2j*x= 0.2m
2j*x= 0.2*(7/3)l
2j*x= 0.2*(7/3)*3k
2j*x= 0.2*7*5j --> x=0.1*7*5 (inaccurate calc.)
x=.1*7*5
%x=(70*5)%

Where am I going wrong?

OA: D
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by jaguar123 » Fri Jul 15, 2011 10:55 am
Hi,
Can anyone help with the method i tried below.
From the given data, i formed the ratios

J/K = 1/5 , K/L = 1/3 ,L/M = 3/7.

Inorder to relate J and M, i made the intermediates to be in common terms.

J/K = 1/5 , K/L = 5/15, L/M = 15/105.

I presumed , Now when J=1, M = 105. But these values
when substitued in the eqn

0.2M = 2.0 * J * X is not working.
Kindly help
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by sandeeptalla450 » Fri Jul 15, 2011 11:06 am
jaguar123 wrote:Hi,
Can anyone help with the method i tried below.
From the given data, i formed the ratios

J/K = 1/5 , K/L = 1/3 ,L/M = 3/7.

From the question, 7L/8=3M/4. So, L/M=6/7
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by MM_Ed » Sun Sep 25, 2011 9:28 am
Answer is D.

My way of solving this is to reduce the general case into a specific case (sorry, algebra!)

Let:
j = 4

Which gives:
k = 20
l = 60
m = 140

0.2m = 28
2j = 8

0.2m/2j = 28/8 = 3.5 = 350% (question asks for percent)

Easy-peasy : )
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by Tani » Sun Sep 25, 2011 2:08 pm
Great approach! Always look for the possibility of picking numbers in a problem like this,
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by MBA.Aspirant » Fri Oct 14, 2011 12:24 am
3.5 times or 350%
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by jayavignesh » Fri Oct 14, 2011 4:51 am
hai1 wrote:If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j ?


a 0.35 b 3.5 c. 35 d. 350 e. 3500

My approach:
1.25J=0.25K => K=5J
1.5K=0.5l => l=3K
0.75m=1.75l => m=(7/3)l

0.2m=2j*x; X=?

2j*x= 0.2m
2j*x= 0.2*(7/3)l
2j*x= 0.2*(7/3)*3k
2j*x= 0.2*7*5j
x=.1*7
%x=70%

Where am I going wrong?

OA: D
125% of j is equal to 25% of k
750% of j is equal to 150% of k

150% of k is equal to 50% of l
750% of J is equal to 50% of l

2625% of j is equal to 175% of l
2625% of j is equal to 75% of m

Therefore,20% of m is (2625/75 )*20= x % of 200% of J

Ans :350
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by zooki » Sat Oct 15, 2011 8:04 am
125%=5/4, 25%=1/4, 150%=3/2, 175%=7/4 75%=3/4
Most of the Guide ask us to memorize these to save time.

using these can easily get you the formula to solve for 20%of m=350
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by bharti06 » Mon Jan 30, 2012 3:48 am
MM_Ed wrote:Answer is D.

My way of solving this is to reduce the general case into a specific case (sorry, algebra!)

Let:
j = 4

Which gives:
k = 20
l = 60
m = 140

0.2m = 28
2j = 8

0.2m/2j = 28/8 = 3.5 = 350% (question asks for percent)

Easy-peasy : )
Hi MM_Ed,

Can you please suggest what made you choose 4 for J? Thanks.
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by Tani » Mon Jan 30, 2012 7:41 am
your first task was to find 125% of something. That would be easiest if your original number was a multiple of four.
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by MM_Ed » Mon Jan 30, 2012 6:34 pm
bharti06 wrote:
MM_Ed wrote:Answer is D.

My way of solving this is to reduce the general case into a specific case (sorry, algebra!)

Let:
j = 4

Which gives:
k = 20
l = 60
m = 140

0.2m = 28
2j = 8

0.2m/2j = 28/8 = 3.5 = 350% (question asks for percent)

Easy-peasy : )
Hi MM_Ed,

Can you please suggest what made you choose 4 for J? Thanks.
The questions mentions 25% and 125%, so I went for 4 (25% of 4 = 1) for convenience : )
If you found one of my answers useful, hit the shiny Thanks button! : )
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