Question

sayna can ambroied bedsheet in 15 days.her sister in law can
do it in 10 days.they start ambroding bedsheet together ,but 2 days latter her
sister in law gives up the work & goes her to parents .in how manys days
finished remaining work?

Answer 1

SAnya completes work in 15 days
therefore ,
work done by Sania = 1 /15 part of work .
%age of work done by sania in one day = 1/15 * 100
                                  = 6.66%

Sanyas sister in law completes work in 10 days .
therefore ,
work done by sanya's sister in law in one day = 1/10 part of work.
%age of work done by sanya's sister in law in one day = 1/10*100
                    = 10%

hence the %age of work done by sanya and her Sister in law in one day = 6.66% + 10 %
                = 16.66%

since sanya and her sister in law worked for two days , hence work done by them in 2 days =
        = 16.66 *2
        = 33.32%

therfore the remaining % of work = 100 - 33.32%
      =66.66 %

since sanya completes 6.66% of work in one day .
therefore 66.66% of work will bw done by sania in 10 days.

hence it will take 10 days to finish the remaining work.

Answer 2

Sanya's one day work = 1/15
sanya's sis in law one day work = 1/10

they work for 2 days together
2((1/15)+(1/10)) = 50/150 i.e, 1/3 work is finished..

the remaining 2/3 work should be done by sanya only

(2/3) * (15days) = 10days

Sanya taken 10 days to finish the Remaining work...