<PRE><B>Question 301708</B>
Working together, Jenny and Natalie can mop a warehouse in 5.14 hours. Had she done it alone it would have taken Natalie 12 hours. How long would it take Jenny to do it alone? 
.
Let x = number of hours if Jenny worked alone
then
5.14(1/x + 1/12) = 1
Multiplying both sides by 12x we have:
5.14(12 + x) = 12x
61.68 + 5.14x = 12x
61.68 = 6.86x
9 hours = x
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