GMAT CLUB OLYMPICS: 9/20th of water from Jar X is poured to jar Y. Aft

Question

9/20th of water from Jar X is poured to jar Y. After this, does jar Y contain more water than jar X ?

(1) After pouring the water, the amount of water in Jar Y increased by more than 2/3 rds

(2) After pouring the water, the amount of water in Jar Y increased by less than 4/5 ths

M36-24

Loser94 · Answer

9/20th of water from Jar X is poured to jar Y. After this, does jar Y contain more water than jar X ?

(1) After pouring the water, the amount of water in Jar Y increased by more than 2/3 rds

(2) After pouring the water, the amount of water in Jar Y increased by less than 4/5 this

Lets solve this through plug in values
initial volume in jar X 20
initial volume in jar Y a
9 lt is transfer to Y
now volume in JAr Y a+9

Statement 1
volume in JAr Y increased by more than 2/3 
9=2/3a 
a(lhighest value )= 27/2=13.5

so volume in Jar Y will be less than 13.5+9=22.5 & volume in Jar X is 11
Not sufficient

State 2
volume in JAr Y increased by less than 4/5 
9=4/5a 
a(Lowest value)= 45/4= 11.2
so volume in Jar Y is 11.2+9=22.5 & volume in Jar X is 11
Sufficient

IMO-B

Kinshook · Answer

Given: 9/20th of water from Jar X is poured to jar Y.
Asked: After this, does jar Y contain more water than jar X ?

Before pouring: -
Let the water in jar X be x litres
and the water in jar Y be y litres.

After pouring: -
Water in jar X = x - 9x/20 = 11x/20
Water in jar Y = y + 9x/20

Asked: -
Is (y + 9x/20) - 11x/20 = y - x/10 > 0?

(1) After pouring the water, the amount of water in Jar Y increased by more than 2/3 rds
9x/20 > 2y/3
y < 27x/40
NOT SUFFICIENT

(2) After pouring the water, the amount of water in Jar Y increased by less than 4/5 ths
9x/20 < 4y/5
y > 45x/80 = 9x/16 > x/10; since x>0
SUFFICIENT

IMO B

rvgmat12 · Answer

Y+9/20X>11/20X Y>X/10? Statement 1: Y+9/20X > 5/3Y Y<27X/40 Not sufficient Statement 2: Y+9/20X < 9/5Y Y>9/16X Sufficient B

albsilvag · Answer

As per the question, we need to solve the following:

is \((y+\frac{9}{20}x) > (x-\frac{9}{20}x)\)? --> Moving the "x" to the right and operating, this can be translated into: is y > 1/10*x?

1) we are told that after pouring the water, the amount in jar y increased by more than 2/3: \(\frac{9}{20}x > \frac{2}{3}y\) --> simplifying, we get that \(y < \frac{27}{40}x\); Therefore, y could be \(\frac{27}{40}x\), but also \(\frac{1}{100}x\) --> NOT SUFFICIENT
2) \(\frac{9}{20}x < \frac{4}{5}y\) --> Simplifying, we get that \(y > \frac{45}{80}x\), which is \(> \frac{1}{10} x\) --> SUFFICIENT

chetan2u · Answer

At times taking some value eases the calculation. Since A and B are related, let us take X has 20 liters. Thus Now, Y has y+9, while x has 11. The question is: Is y+9>11? OR Is y>2? (1) After pouring the water, the amount of water in Jar Y increased by more than 2/3 rds So, the water in Y > y+\frac{2y}{3} That is, y+9> y+\frac{2y}{3}.............2y<27.......y<13.5 If y is 10, yes. If y is 1, no. (2) After pouring the water, the amount of water in Jar Y increased by less than 4/5 ths So, the water in Y > y+\frac{2y}{3} That is, y+9< y+\frac{4y}{5}.............4y>45.......y>10.25>2 SO y is surely more than 2 units. Sufficient B

Bunuel · Answer

Official Solution: \frac{9}{20}^{th} of water from Jar X is poured to jar Y. After this, does jar Y contain more water than jar X ? Say the amount of water in Jar X is x units and the amount of water in Jar Y is y units. The question asks: is x - \frac{9}{20}*x < y + \frac{9}{20}*x ? , which simplifies into is x < 10y ? . (1) After pouring the water, the amount of water in Jar Y increased by more than \frac{2}{3}^{rds} \frac{9}{20}*x > \frac{2}{3}*y ; x > \frac{40}{27}*y So, x can be less than 10y as well as more than 10y . Not sufficient. (2) After pouring the water, the amount of water in Jar Y increased by less than \frac{4}{5}^{ths} \frac{9}{20}*x < \frac{4}{5}*y ; x < \frac{16}{9}*y x < \frac{16}{9}*y gives an YES answer to the question whether x < 10y . Sufficient. Answer: B

bumpbot · Answer

Automated notice from GMAT Club BumpBot: 

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

 This post was generated automatically.

GMAT CLUB OLYMPICS: 9/20th of water from Jar X is poured to jar Y. Aft

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards