Question

In the series, 6 4 1 2 2 8 7 4 2 1 5 3 8 6 2 1 7 1 4 1 3 2 8 6
How many pairs of alternate numbers have a difference of 2 ?

• A. One
• B. Two
• C. Three
• D. Four

Answer 1

Answer: (B)

Two

We proceed by checking the difference between pairs of alternate numbers i.e., (6,1), (4,2), (1,2), (2,8), (2,7), (8,4), (7,2) (4,1), (2,5), (1,3), (5,8), (3,6), (8,2), (6,1), (2,7), (1,1), (7,4), (1,1), (4,3), (1,2), (3,8), and (2, 6). Of these, the pairs with a difference of 2 are (4,2) and (1,3). Clearly, there are two such pairs.