Question 1122714
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<pre>
The entire job consists of 2 + 3 + 5 = 10 equal parts .


Vivek does {{{2/10}}} of the work in 12 days  ====>
His rate is  {{{ ((2/10))/12 }}} =  {{{ 1/60 }}}  of the entire job per day.


Ramesh’s rate is:
{{{ 2*( 1/60 )}}} = {{{ 1/30 }}}  of the entire job per day.


Bhuvan’s rate is:
{{{ 3*( 1/60 )}}} = {{{ 1/20 }}}  of the entire job per day.



    Till this point my solution coincides with that by @josmiceli.


    Starting from the next line, my way is  <U>DIFFERENT</U>.



Their combined rate of work is  {{{1/60}}} + {{{1/30}}} + {{{1/20}}} = {{{(1 + 2 + 3)/60}}} = {{{5/60}}} = {{{1/12}}}   of the entire job per day.


Hence, in 8 days they will complete  {{{8/12}}} = {{{2/3}}} of the job.
</pre>

Solved.