SSC CHSL 7 Mar 2018 Shift 2 Paper

Let quantity of each sample is L.C.M. (4,8,16) = 16 unit
⇒ Milk in first sample = $\frac{1}{\left(1+3\right)}\times 16=4$ unit
and water in first sample = $\mathrm{1}6-4=12$ units
Similarly, milk in second sample = $\frac{3}{\left(3+5\right)}\times 16=6$ units and water = $16-6=10$ units
Milk in third sample = $\frac{11}{\left(11+5\right)}\times 16=11$ units and water = $16-6=10$ units
∴ Ratio of milk and water in the new mixture= $\frac{\left(4+6+11\right)}{\left(12+10+5\right)}$
= $\frac{21}{27}=\frac{7}{9}$