sequence
This topic has expert replies
-
- Master | Next Rank: 500 Posts
- Posts: 113
- Joined: Thu Jul 16, 2009 11:23 am
- Thanked: 15 times
- GMAT Score:730
Okay so this is a simple word problem;
we just look at consecutive pairs that have a negative product;
for 1,-3,2,5,-4,-6
we get product of pair 1 = 1*-3 = -3 (1 variation)
pair 2 = -3 * 2 = -6 (2 variations so far)
pair 3 = 2*5 = 10 (not a variation)
pair 4 = 5*-4 = -20 (3 variations so far)
pair 5 = -4*-6 = 25 (not a variation)
so the answer is 3 variations
we just look at consecutive pairs that have a negative product;
for 1,-3,2,5,-4,-6
we get product of pair 1 = 1*-3 = -3 (1 variation)
pair 2 = -3 * 2 = -6 (2 variations so far)
pair 3 = 2*5 = 10 (not a variation)
pair 4 = 5*-4 = -20 (3 variations so far)
pair 5 = -4*-6 = 25 (not a variation)
so the answer is 3 variations