Count each 7 that is not immediately preceded by 5 but is immediately followed by either 2 or 3. How many such 7s are there?
5, 7, 2, 6, 5, 7, 3, 8, 3, 7, 3, 2,
5, 7, 2, 7, 3, 4, 8, 2, 6, 7, 8.
A
2
B
3
C
4
D
5
Correct Option:
A
Explanation
We need a 7 that is not immediately preceded by 5 but is immediately followed by 2 or 3. The qualifying patterns are 3, 7, 3 and 2, 7, 3. Any 7 immediately preceded by 5 is excluded.
