SOLUTION: Deirdre, Tara, and Caitlin can complete a certain job in 5 days. Deirdre can do the job alone in 12 days. Tara can do the job alone in 10 days. How many days would it take Caitlin
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-> SOLUTION: Deirdre, Tara, and Caitlin can complete a certain job in 5 days. Deirdre can do the job alone in 12 days. Tara can do the job alone in 10 days. How many days would it take Caitlin
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Question 63092This question is from textbook introductory algebra
: Deirdre, Tara, and Caitlin can complete a certain job in 5 days. Deirdre can do the job alone in 12 days. Tara can do the job alone in 10 days. How many days would it take Caitlin alone to complete the job? This question is from textbook introductory algebra
You can put this solution on YOUR website! Deirdre, Tara, and Caitlin can complete a certain job in 5 days. Deirdre can do the job alone in 12 days. Tara can do the job alone in 10 days. How many days would it take Caitlin alone to complete the job?
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Let the completed job = 1:
:
Let x = C"s time alone
: = 1
You can tell by the value of the 1st two fractions that C' contribution to the job will not be much:
:
Mult eq by a common denominator; 60x would be a good one, resulting in
5x(5) + 6x(5) + 60(5) = 60x
25x + 30x + 300 = 60x
25x + 30x - 60x = - 300
-5x = -300
x = -300/-5
x = 60 hrs for C to do the job by herself!!
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:
Check: = 1