-
vivek.kapoor83
- Legendary Member
- Posts: 833
- Joined: Mon Aug 04, 2008 1:56 am
- Thanked: 13 times
Refer to Ron's solution here:
https://www.manhattangmat.com/forums/if- ... -t821.html
gmatprep11
This topic has expert replies
Source: Beat The GMAT — Problem Solving |
-
vittalgmat
- Legendary Member
- Posts: 621
- Joined: Wed Apr 09, 2008 7:13 pm
- Thanked: 33 times
- Followed by:4 members
Ans is A.
Stmt 1 says that the Z is > 5.5 (the mid point of 1 and 10).
So avg of x and 10 will be >= x and <= 10. So A is sufficient.
Commonsense Takeaway:
Avg of two numbers is never less than lesser of the two numbers OR
greater than the greater of the two numbers.
Mathematically, if x and y are two numbers:
x <= avg <= y.
Stmt 2 is obviously insufficient.
HT Helps
Stmt 1 says that the Z is > 5.5 (the mid point of 1 and 10).
So avg of x and 10 will be >= x and <= 10. So A is sufficient.
Commonsense Takeaway:
Avg of two numbers is never less than lesser of the two numbers OR
greater than the greater of the two numbers.
Mathematically, if x and y are two numbers:
x <= avg <= y.
Stmt 2 is obviously insufficient.
HT Helps
