How many such pairs of digits are there in the number 421579368 each of which has as many digits between them in the number as when they are arranged in ascending order?
Answer: D
Given Number: 4 2 1 5 7 9 3 6 8
Ascending order: 1 2 3 4 5 6 7 8 9
Hence the required pairs are 12, 49, 16