(i) 9 and 19

To find: Arithmetic mean between 9 and 19

The formula used: Arithmetic mean between

We have 9 and 19

(ii) 15 and -7

To find: Arithmetic mean between 15 and -7

The formula used: Arithmetic mean between

We have 15 and -7

(iii) -16 and -8

To find: Arithmetic mean between -16 and -8

The formula used: Arithmetic mean between

We have -16 and -8