Question 534142
Work problems like this are fraction problems.
Lisa does the whole job in 65 minutes, so she does 1/65 of the job per minute.
Bill does 1/45 of the job per minute.
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(1/65+1/45)*x minutes = 1 whole job completed
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(45+65)/(45*65) * x = 1
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110/2925 * x = 1
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22/585 * x = 1
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22x = 585
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x = 585/22
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x = 26.590 min
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Working together they can do the job in about 26.6 minutes.
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Always check your work.
1/45 * 26.6 = .591 = amount of the job done by Bill
1/65 * 26.6 = .409 = amount of the job done by Lisa
Total = 1 whole job.
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Done.