Question

Consider two mixtures, one containing milk, water and an unknown miscible liquid in the ratio 2 : 5 : 13, and other mixture containing milk and water in the ratio 3 : 7. Two litres of first mixture and 5 litres of second mixture are mixed. What will be the fraction of water in resulting mixture ?

Answer 1

2:5:13 the ratio of mixtures in first liquid
2/20 parts of milk
5/20 of water
13/20 unknown fluid
2 liters of it is taken
water quantity in 2 liters
5/20*2=0.5 ----- (1)

second mixture contains milk and water in 3:7
7/10 parts of water
5 liters of it is taken
7/10*5 = 3.5 ------- (2)

adding 1 and 2 we get 4 liters
the fraction of water in the new mixture is 4/7