$$\\$$Two Team A&B of workers at a bridge site. Each team consist of W workers. On a particular day, a worker was shifted from team A to team B . Now if the ratio of the amount of workdone by teamA in (W+1) he & by teamB in (W+2) hr is 10:12 rsp. Find W?
$${team}\:{A}:\:{W}−\mathrm{1}\:{workers} \\$$$${works}\:{done}\:{in}\:{W}+\mathrm{1}\:{hours}=\left({W}−\mathrm{1}\right)\left({W}+\mathrm{1}\right) \\$$$$\\$$$${team}\:{B}:\:{W}+\mathrm{1}\:{workers} \\$$$${works}\:{done}\:{in}\:{W}+\mathrm{2}\:{hours}=\left({W}+\mathrm{1}\right)\left({W}+\mathrm{2}\right) \\$$$$\\$$$$\frac{\left({W}−\mathrm{1}\right)\left({W}+\mathrm{1}\right)}{\left({W}+\mathrm{1}\right)\left({W}+\mathrm{2}\right)}=\frac{\mathrm{10}}{\mathrm{12}}=\frac{\mathrm{5}}{\mathrm{6}} \\$$$$\mathrm{6}{W}−\mathrm{6}=\mathrm{5}{W}+\mathrm{10} \\$$$$\Rightarrow{W}=\mathrm{16} \\$$
$$\mathrm{i}\:\mathrm{got}\:\mathrm{W}=\mathrm{4}. \\$$$$\mathrm{both}\:\mathrm{team}\:\mathrm{A}\:\mathrm{and}\:\mathrm{B}\:\mathrm{have}\:\mathrm{the}\:\mathrm{same} \\$$$$\mathrm{worker} \\$$