Correct Answer - Option 3 : 16

**Given:**

The average of 7 number = 8

The average of 8 number = 9

**Calculation:**

The total sum of 7 number = 7 × 8 = 56

The total sum of 8 number = 8 × 9 = 72

then,

The added number = total sum of 8 no.- total sum of 7 no.

72 - 56 = 16

**∴The added number is 16 .**