SOLUTION: Two contractors were working together to finish concrete. One can finish 25 square yards in 4 hours. The other can finish 25 square yards in 5 hours. How much concrete can they fin

Question 446147: Two contractors were working together to finish concrete. One can finish 25 square yards in 4 hours. The other can finish 25 square yards in 5 hours. How much concrete can they finish in 8 hours working together?
Found 2 solutions by Alan3354, josmiceli:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
The 1st does 25/4 per hour.
The 2nd does 25/5 per hour.
Together, they do 25/4 + 5 per hour
--> 45/4 per hour * 8 hours
= 90 sq yds

Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Add their rates of working to get their
rate working together
rate = ( square yds finished ) / ( time to finish them )

The numerators are in units of square yards
Multiply both sides by

They can finish 90 square yards working together

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