IMO B
3^(-x-y) / 3^(-x+y)
=>3^-x . 3^-y . 3^x .3^-y
=>3^(-2y)
Hence, B
Exponents
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
- krishnasty
- Master | Next Rank: 500 Posts
- Posts: 142
- Joined: Mon Jan 10, 2011 8:03 am
- Thanked: 19 times












