SOLUTION: clarissa can clean a house in 10 days. shawna can clean a house in 15 days. how many days do they take to clean the house together?

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Question 505239: clarissa can clean a house in 10 days. shawna can clean a house in 15 days. how many days do they take to clean the house together?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add their rates of cleaning
Clarissa's rate: 1 house / 10 days
Shawna's rate: 1 house / 15 days
Rate working together: 1 house / x days
Add the rates:
+1%2F10+%2B+1%2F15+=+1%2Fx+
Multiply both sides by +30x+
+3x+%2B+2x+=+30+
+5x+=+30+
+x+=+6+
Working together, it takes them 6 days to clean the house