SOLUTION: A AND B WORKING TOGETHER TAKE 8 AND 18 LESS DAYS THAN A ALONE AND B ALONE RESPECTIVELY TO DO A WORK. THE NUMBER OF DAYS TAKEN BY A AND B WORKING TOGETHER TO DO THE WORK IS?

Question 1052907: A AND B WORKING TOGETHER TAKE 8 AND 18 LESS DAYS THAN A ALONE AND B ALONE RESPECTIVELY TO DO A WORK. THE NUMBER OF DAYS TAKEN BY A AND B WORKING TOGETHER TO DO THE WORK IS?
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39838)   (Show Source): You can put this solution on YOUR website!
Keep rechecking and thinking between this table of data and the description, until you understand how this table shows the description.

PERSON TIME for 1 job A x B y A&B x-8 and y-18

You need to understand this: The combined work rate of A and B is the sum of their individual rates. The unit for these rates is JOBS/DAY, or WORK/DAYS, whichever way you choose. Keep on reviewing all of this until it makes sense.

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Answer by ikleyn(53942)   (Show Source): You can put this solution on YOUR website!
.
A AND B WORKING TOGETHER TAKE 8 AND 18 LESS DAYS THAN A ALONE AND B ALONE RESPECTIVELY TO DO A WORK.
THE NUMBER OF DAYS TAKEN BY A AND B WORKING TOGETHER TO DO THE WORK IS?
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Let x = THE NUMBER OF DAYS TAKEN BY A AND B WORKING TOGETHER TO DO THE WORK. The the number of days for A to do the job working alone is (x+8), and the number of days for B to do the job working alone is (x+18). Then the standard equation for joint work is = . To solve it, multiply everything by x*(x+8)*(x+18). You will get x*(x+18) + x*(x+8) = (x+8)*(x+18). Simplify: = , or = 144. Hence, x = = 12. Answer. 12 days.

A wide variety of similar joint-work problems were solved with detailed explanations in the lessons
    - Using Fractions to solve word problems on joint work,
    - Solving more complicated word problems on joint work,
    - Selected joint-work word problems from the archive
in this site.

Read them and become an expert in solving joint-work problems.

Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this textbook under the topic "Rate of work and joint work problems" of the section "Word problems".

As a concluding remark, ignore writing by the other tutor, named "josgarithmetic".
The way he proposes is the way to nowhere.