Series A consist of four consecutive odd numbers whose average is 22 and series B consist of four consecutive even numbers whose average is 17. Find the difference between the largest number of series A and smallest number of series B.

Correct option is B

Let the number of series A be a, a+ 2, a+4, a+6
Let the number of series B be b, b+ 2, b+4, b+6
For series A
a+a+2+a+4+a+6=22×4
4a = 88 -12
4a = 76
a = 19
For series B
b + b+ 2 + b+4 + b+6 = 17 ×4 = 68
4b = 56
b = 14
Required difference = 25 – 14 = 11