The combined average of the two groups is 20.44.
To find this, we can use the following steps:
The number of quantities in group A is 10, and the number of quantities in group B is 8.
The individual average of group A is 24, and the individual average of group B is 16.
The combined total of the two groups is 10 * 24 + 8 * 16 = 240 + 128 = 368.
The total number of quantities in the two groups is 10 + 8 = 18.
Therefore, the combined average of the two groups is 368 / 18 = 20.44.