SSC MTS Model Paper 6

Let cost of 1 litre milk be Rs. 1
Milk in 1 litre mix. in A = $\frac{8}{13}$ litre
C.P. of 1 litre mix. in A = Rs. $\frac{8}{13}$
5 Milk in 1 litre mix. in B = $\frac{5}{7}$litre
C.P. of 1 litre mix. in B = Rs. $\frac{5}{7}$
Milk in 1 litre of final mix.
$=\left(\frac{900}{13}\times \frac{1}{100}\times 1\right)=\frac{9}{13}$ litre
Mean price = Rs. $\frac{9}{3}$
By the rule of alligation, we have:

∴ Required ratio =$\frac{2}{91}$ :$\frac{1}{13}$ = 2 : 7