Answer:
Change = -(1/2) * 30 = -15 inches
Explanation:
If the water level decreases by 1/2 inch each day, the change in the water level in one day is -1/2 inch.
So, after t days, the total change in the water level can be calculated as:
Total change = -(1/2) * t inches
So, after 30 summer days, the total change is:
Change = -(1/2) * 30 = -15 inches
So the water level of the pool after 30 summer days has decreased by 15 inches.