6, 11, 21, 36, 56, ?
what will replace the question mark in the series ?

Answer: Option A

Explanation:

Pattern is +5, +10, +15, + 20. So next will be 56+25 = 81

Answer: Option B

Explanation:

Above series contains prime number series. So after 11, 13 is next prime number.

Answer: Option B

Explanation:

Each number in the series is the preceding number multiplied by 3 and then decreased by 2.

Answer: Option A

Explanation:

Pattern in the series is *2+1, *2+2, *2+3,.....

Term which replaces the question mark in the series is
121 * 2 + 6 = 248

Answer: Option A

Explanation:

We can judge that it is A.P.
With 6 as difference
nth term in A.P. = a+(n-1)d
a= 3, n = 21, d = 6
So, 21st term will be = 3+(20)6 = 123