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**symmetry** A 5 horsepower (hp) pump can empty a pool in 5 hours. A smaller, 2hp pump empties the same pool in 8 hours. The pumps are used together to begin emptying this pool. After 2 hours, the 2hp pump breaks down. How long will it take the larger pump to empty the pool?

SIDE QUESTIONS:

(1) Is this question similar to math questions about working alone and working together?

(2) How do you set up an equation for such a question?

I got lost when the 2hp pump broke down after 2 hours.