John weighs twice as much as Susan. Susan's weight is 60% of

Question

John weighs twice as much as Susan. Susan's weight is 60% of Sam's weight. Mark weighs 50% of Lynn's weight. Lynn weighs 190% of John's weight. Which of these 5 people weighs the least? 
 
A. John 
B. Susan 
C. Sam 
D. Mark 
E. Lynn

subhashghosh · Answer

Let J – John’s weight
S – Susan’s weight
M – Mark’s weight
A – Sam’s weight
L – Lynn’s weight
J = 2S
S = 0.6A
M = 0.5L
L = 1.9J
Let us convert these weights to one variable
S = J/2
A = S/0.6 = J/1.2 = 5J/6
L = 1.9J
M = 0.5 * 1.9J = 0.95J
So Susan has the least weight.

Answer - B

Bunuel · Answer

John weighs twice as much as Susan --> J=2S --> John cannot weigh the least;
Susan's weight is 60% of Sam's weight --> S=0.6*Sam --> Sam cannot weigh the least;
Mark weighs 50% of Lynn's weight --> M=0.5*L --> Lynn cannot weigh the least;
Lynn weighs 190% of John's weight --> L=1.9*J --> John cannot weigh the least (we already know that);

As you can see the answer is either Susan (S) or Mark (M). To compare their weights we should express their weights in regards of the same person: M=0.5*L=0.5*(1.9*J)=0.85*J and from J=2S, S=0.5*J --> Susan weights the least: Susan's weight is 50% of that of John and Mark's weight is  more than 50%  of that of John.

Answer: B.

Hope it's clear.

GSBae · Answer

This question requires no algebra, just a parsing of the text.

0---------|Susan|---------|Sam|--|Max|--|John|------------------|Susan|.

John weighs twice as much as Susan.  Self explanatory.
 Susan's weight is 60% of Sam's weight.  This means Sam weighs more than Susan, but less than John, because Susan is 50% of John's weight. (1/.6 = 5/3 = 1.66%. This means Sam weights 1.6 times Susan, which is less than 2).
 Mark weighs 50% of Lynn's weight.   Let's come back to this.
 Lynn weighs 190% of John's weight.   We can approximate 190% to be almost twice as much, so Lynn weighs almost twice as much as John. Now, Mark weighs half of Lynn, so a little bit less than John.

We don't know the exact relation between Max and Sam, but it doesn't matter because we still know that Susan is much less than all of them.

Answer: B

ANOTHER APPROACH:

Just use POE.

John weighs twice as much as Susan.  John weighs more than Susan - eliminate. 
 Susan's weight is 60% of Sam's weight.  Sam weighs more than Susan - eliminate. 
 Mark weighs 50% of Lynn's weight.   Wait on this one. 
 Lynn weighs 190% of John's weight.   Lynn weighs more than John. Eliminate Susan.

Now we've narrowed down our potential solutions to 2 just by reading the options. We have either Susan or Mark. Now - Susan weighs almost twice as much as John, and Mark weighs half of Lynn, so Mark and John weigh very close to one another. John however is twice as much as Susan. So Susan still weighs considerably less.

Answer: B

TARGET730 · Answer

Thought i will share an easy way that i found

Take John's weight as 100

J=100
So Lynn = 190
Mark = 95
Susan = 50
Sam = 500/6

Lowest is Susan

bumpbot · Answer

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John weighs twice as much as Susan. Susan's weight is 60% of

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John weighs twice as much as Susan. Susan's weight is 60% of

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