Question 1088782
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<pre>
From 9:00 am to 10:00 am, Mr.X will complete {{{1/3}}} of the activity, so {{{2/3}}} will remain uncompleted.


The rate of work for X is {{{1/3}}} of the job per hour.


The rate of work for Y is {{{1/6}}} of the job per hour.


So, their combined rate of work is {{1/3+1/6}}} = {{{2/6+1/6}}} = {{{3/6}}} = {{{1/2}}} of the job per hour.


Thus they need {{{((2/3))/((1/2))}}} = {{{(2*2)/3}}} = {{{4/3}}} hours = 1 hour and 20 minutes to complete the job.


So, Mr.X and Mr.Y  will complete their activity 1 hour and 20 minutes after 10:00 am, i.e. at 11:20 am.
</pre>

Solved.



It is a typical joint work problem.


There is a wide variety of similar solved joint-work problems with detailed explanations in this site. &nbsp;See the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Rate-of-work-word-problems/Word-problems-WORKING-TOGETHER-by-Fractions.lesson>Using Fractions to solve word problems on joint work</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Rate-of-work-word-problems/Solving-more-complicated-word-problems-on-joint-work.lesson>Solving more complicated word problems on joint work</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Rate-of-work-word-problems/Selected-problems-from-the-archive-on-joint-work-word-problems.lesson>Selected joint-work word problems from the archive</A> 



Read them and get be trained in solving joint-work problems.


Also, &nbsp;you have this free of charge online textbook in ALGEBRA-I in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.


The referred lessons are the part of this textbook under the topic 
"<U>Rate of work and joint work problems</U>" &nbsp;of the section &nbsp;"<U>Word problems</U>".