Answer:
The total cost to install the 1,200 ft of the pipe is $21000.
Explanation:
Consider the provided information.
You buy 900 ft pipe with a cost of $15 per foot and the remaining 300 ft pipe with a cost of $25 per foot.
Therefore, the total cost is:




Hence, the total cost to install the 1,200 ft of the pipe is $21000.