D. 24.75
Step-by-step explanation:
We start by getting the purchase price of the clock.
To do this, we first find what 25% of 30 is and then subtract that from 30:
.25 x 30 = 7.5
30 - 7.5 = 22.5 is the purchase price
Then, we find the price of delivery.
We first find what 10% of 22.5 is:
.10x22.5= 2.25
Finally, we add the purchase price and price of delivery:
22.5 + 2.25 = 24.75