A, B can dig a well in 10 days and 12 days respectively. If Rs.11 is for total work what is A share.

A’ s one day’s work = $\frac{1}{10}$ B’ s one day’s work = $\frac{1}{12}$ Ratio of (A+B)’s one day work = $\frac{1}{10} : \frac{1}{12}$ = 6 : 5 Amount should

A, B complete a work in 25, 20 days respectively. after working together for 5 days A left. B complete the work in

(A+B)’s 5 days work = 5$\lbrack \frac{1}{25}+\frac{1}{20}\rbrack$ = 5$\lbrack \frac{4+5}{100}\rbrack$ = 5 $\lbrack \frac{9}{100}\rbrack$ = $\frac{9}{20}$ Remaining work = 1 – $\frac{9}{20}$ = $\frac{11}{20}$ B can

A and B together complete a work in 12 days. B alone can complete the work in 28 days. A alone can do the work in how many days.

(A+B)’s one day’s work = $\frac{1}{12}$ B’s one day work = $\frac{1}{28}$                                                        $\lbrack (A+B)- (B) = A\rbrack$ A’s one day work = $\frac{1}{12}$ – $\frac{1}{28}$ = $\frac{7-3}{84}$ = $\frac{4}{84}$

A’s one day’s work = $\frac{1}{6}$ B’s one day’s work = $\frac{1}{8}$ C’s one day’s work = $\frac{1}{12}$ (A+B+C)’s one day work = $\frac{1}{6}$ + $\frac{1}{8}+\frac{1}{12}$ = $\frac{4+3+2}{24}$ = $\frac{9}{24}$
A’s one day’s work = $\frac{1}{20}$ B’s one day’s work = $\frac{1}{30}$ (A + B)’s one day work = $\frac{1}{20}$ + $\frac{1}{30}$ = $\frac{3 + 2}{60}$ = $\frac{5}{60}$ = $\frac{1}{12}$