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GmatTakerNo.1
- Senior | Next Rank: 100 Posts
- Posts: 37
- Joined: Sat Apr 24, 2010 8:27 am
I think the solution is easy, but I´m missing the last thought to solve it.
9. If the sequence x1, x2, x3, ..., xn, ... is such that x1 = 3 and xn+1= 2xn - 1 for n ≥ 1, then x20 - x19 equals?
a) 219
b) 220
c) 221
d) 220 - 1
e) 221 - 1
The answer is A. Maybe you can help me with this one.
9. If the sequence x1, x2, x3, ..., xn, ... is such that x1 = 3 and xn+1= 2xn - 1 for n ≥ 1, then x20 - x19 equals?
a) 219
b) 220
c) 221
d) 220 - 1
e) 221 - 1
The answer is A. Maybe you can help me with this one.
