Answer:
75 feet
Explanation:
If the plumber used 25 feet of pipe in 2 months, then he should need 25 feet multiplied by 6 months and divided by 2 months, the calculation can be deduced from the following reasoning:
If in 2 months he used 25 feet, how many feet will he use in 6 months?
That's
2 months ------------------ 25 feet
6 months ------------------ X
X = 25 feet x 6 months / 2 months
X = 75 feet