A. 20

B. 21

C. 28

D. 32

### Solution(By Apex Team)

Let Ajit’s average be x for 9 innings. So, Ajit scored 9x run in 9 innings. In the 10th inning, he scored 100 runs then average became (x+8). And he scored (x + 8) × 10 runs in 10 innings. Now, $\begin{array}{l} \Rightarrow 9 x+100=10 \times(x+8) \\ \text { or, } 9 x+100=10 x+80 \\ \text { or, } x=100-80 \\ \text { or, } x=20 \\ \text { New average }=(x+8) \\ =28 \text { runs } \end{array}$

A. 20
B. 21
C. 28
D. 32

A. 18
B. 20
C. 24
D. 30

A. 10 years
B. 10.5 years
C. 11 years
D. 12 years