36) For a finite set of nonzero numbers, the number of varia

[varun289]

36) For a finite set of nonzero 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 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

[hemant_rajput]

36) For a finite set of nonzero 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 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

IMO C

only 3 pair are there sequence which meets the criteria of being consecutive and their product is negative.

1 , -3
-3 , 2
5 , -4

[Blue_Skies]

Straighforward. Count the pairs as per the definition. Ans C