Is the Answer E? I missed the OA.
Please share the approach.
GMAT Prep - Inequalities
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- bubbliiiiiiii
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- krishnasty
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IMO E
Option a :
1. lets say x = 4, z=5 ( closer to 10)
avg : 10+4 =14/2 =7 hence, z is less than avg
2. lets say x=4 z= 9 (closer to 10). in this case, z is higher than avg.
INSUFFICIENT
Option b:
1. lets say x =1. Hence, z = 5(1) = 5
avg : 10+1 = 11/2 =5.5..hence, z is less than avg
2. lets say x=2. hence, z = 5(2) =10
avg = 10+2 =12/2 =6. hence, z is more.
INSUFFICIENT
combining both,
again, x = 1, z = 5 (closer to 10). z is less than avg
also, x=2, z=10 (closer to 10). z is more than avg.
INSUFFICIENT
Option a :
1. lets say x = 4, z=5 ( closer to 10)
avg : 10+4 =14/2 =7 hence, z is less than avg
2. lets say x=4 z= 9 (closer to 10). in this case, z is higher than avg.
INSUFFICIENT
Option b:
1. lets say x =1. Hence, z = 5(1) = 5
avg : 10+1 = 11/2 =5.5..hence, z is less than avg
2. lets say x=2. hence, z = 5(2) =10
avg = 10+2 =12/2 =6. hence, z is more.
INSUFFICIENT
combining both,
again, x = 1, z = 5 (closer to 10). z is less than avg
also, x=2, z=10 (closer to 10). z is more than avg.
INSUFFICIENT
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Appreciation in thanks please!!
Appreciation in thanks please!!
- gmatboost
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In this case, z is not closer to 10 than it is to x.1. lets say x = 4, z=5 ( closer to 10)
avg : 10+4 =14/2 =7 hence, z is less than avg
In fact, by definition, if x<10 and z is closer to 10 than it is to x, it must be above the average of 10 and x, since the average of 10 and x is exactly halfway between 10 and x.
So Statement 1 is sufficient.
Statement 2 can also be approached algebraically:
5x > (x+10)/2 ?
10x > (x+10) ?
9x > 10 ?
x > 10/9 ?
[spoiler]Since we don't know whether this is true or not, inssufficient[/spoiler]
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- bblast
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Given x<10, question is (x+10)/2 < Z
1> z is closer to 10 than it is to x can be written in an equation as -> z-x > 10-z
10-z < z-x
x+10 < 2z
(x+10)/2 < Z sufficient to answer a YES.
also if u visualize on a number line .
0-------x------------------------------------(x+10)/2---------z----------10
Z is more towards 10, therefore the weighted average of 10 and x will always be less than z as shown above.
2>(x+10)/2< Z (from question)
put z = 5x
(x+10)/2 < 5x
x+10 <10x
9x > 10 . multiple value of x will satisfy of dis-satisfy this with x<10 -> insufficeint.
pick A
1> z is closer to 10 than it is to x can be written in an equation as -> z-x > 10-z
10-z < z-x
x+10 < 2z
(x+10)/2 < Z sufficient to answer a YES.
also if u visualize on a number line .
0-------x------------------------------------(x+10)/2---------z----------10
Z is more towards 10, therefore the weighted average of 10 and x will always be less than z as shown above.
2>(x+10)/2< Z (from question)
put z = 5x
(x+10)/2 < 5x
x+10 <10x
9x > 10 . multiple value of x will satisfy of dis-satisfy this with x<10 -> insufficeint.
pick A
Cheers !!
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Quant 47-Striving for 50
Verbal 34-Striving for 40
My gmat journey :
https://www.beatthegmat.com/710-bblast-s ... 90735.html
My take on the GMAT RC :
https://www.beatthegmat.com/ways-to-bbla ... 90808.html
How to prepare before your MBA:
https://www.youtube.com/watch?v=upz46D7 ... TWBZF14TKW_
- krishnasty
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ooopss...you are absolutely right...i missed the 'than x' part in the line one...
as stated above, statement 1 is sufficient..thnx for pointing out guys..
as stated above, statement 1 is sufficient..thnx for pointing out guys..
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Appreciation in thanks please!!
Appreciation in thanks please!!