The daily wages of A and B respectively are Rs. 3.50 and Rs. 2.50. When A finishes a certain work, he gets a total wage of Rs. 63. When B does the same work, he gets a total wage Rs. 75. If both of them do it together what is cost of the work ?

Solution(By Examveda Team)

$$\eqalign{ & {\text{Worked day of A}} \cr & = \frac{{63}}{{3.50}} = 18{\text{ days}} \cr & {\text{Worked day of B}} \cr & = \frac{{75}}{{2.50}} = 30{\text{ days}} \cr & {\text{Now, }} \cr} $$
L.C.M. of Total Work =90
One day work of A = $$\frac{{90}}{{18}}$$ = 5 unit/day
One day work of B = $$\frac{{90}}{{30}}$$ = 3 unit/day
$$\eqalign{ & {\text{Required time}} \cr & = \frac{{90}}{8} = \frac{{45}}{4}{\text{ days}} \cr & {\text{Cost}} = {\text{day}} \times \left( {{\text{wages of A}} + {\text{B}}} \right) \cr & = \frac{{45}}{4} \times \left( {3.50 + 2.50} \right) \cr & = {\text{Rs}}.\,67.50 \cr} $$