Source: GMAT Prep
For a finite sequence of non zero numbers, the number of variations in sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence 1, -3, 2, 5, -4, -6?
A. 1
B. 2
C. 3
D. 4
E. 5
The OA is C
For a finite sequence of non zero numbers, the number of variations in sign is defined as the number of pairs of...
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We're asked to examine every pair of consecutive terms. If the product of those two terms is negative, this counts as one variation.BTGmoderatorLU wrote: ↑Fri Aug 13, 2021 6:38 amSource: GMAT Prep
For a finite sequence of non zero numbers, the number of variations in sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence 1, -3, 2, 5, -4, -6?
A. 1
B. 2
C. 3
D. 4
E. 5
The OA is C
Let's examine the pairs of consecutive terms in the sequence 1, -3, 2, 5, -4, -6
1 and -3: product is negative
-3 and 2: product is negative
2 and 5: product is positive
5 and -4: product is negative
-4 and -6: product is positive
Since 3 pairs of consecutive terms have negative products, the correct answer is C
Cheers,
Brent