If x is a positive number less than 10, is z gater than the average of x and 10?
1) on the number line, z is closer to 10 than to x
2) z=5x
Y/N
This topic has expert replies
if x = 1 then avg of 1 & 10 = 5.5......I
if x = 3 then avg of 3 & 10 = 6.5.......II
a)
x = 1 & let z = 9 greater than avg ...... from I
x = 1 & let z = 2 smaller than avg ....... from I
Insuff
b)
if x = 1 then z = 5 smaller than avg ....... from I
if x = 3 then z = 15 greater than avg ........ from II
Insuff
Both together Insuff...
Ans E.
if x = 3 then avg of 3 & 10 = 6.5.......II
a)
x = 1 & let z = 9 greater than avg ...... from I
x = 1 & let z = 2 smaller than avg ....... from I
Insuff
b)
if x = 1 then z = 5 smaller than avg ....... from I
if x = 3 then z = 15 greater than avg ........ from II
Insuff
Both together Insuff...
Ans E.
- simplyjat
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The second option is not possible as Z will be closer to X rather than 10.Suyog wrote: x = 1 & let z = 9 greater than avg ...... from I
x = 1 & let z = 2 smaller than avg ....... from I
Now look at it this way, if Z is equidistant from X and 10, then Z is equal to the average of 10 & X. You need to visualize this....
Now if Z is closer to X, Z is less than average of X & 10, and if Z is closer to 10, Z is greater than the average of X & 10
simplyjat
simplyjat that was indeed a great great explanation and approach!!
...I am not a fan of picking numbers (even though some times we must)because its both time consuming and you never know if it will work for other numbers or if there ia an exception..so this explanation of why A is SUFF is really the one!.
:D
...I am not a fan of picking numbers (even though some times we must)because its both time consuming and you never know if it will work for other numbers or if there ia an exception..so this explanation of why A is SUFF is really the one!.
:D
Was just looking at this one, I think it should be solved like this
1) 10-z < z-x which resolves to 5+x/2 <z> average
SUFF
2) You'd have to sub # in there, cuz you can't use the condition given in 1) for 2)
x =1 , z = 5, A = 5.5, then z <A> A
INSUF
so answer is A
1) 10-z < z-x which resolves to 5+x/2 <z> average
SUFF
2) You'd have to sub # in there, cuz you can't use the condition given in 1) for 2)
x =1 , z = 5, A = 5.5, then z <A> A
INSUF
so answer is A