Aptitude Day 73

Ratio and Proportion:

1. If a:b:c = 3:4:5, then a/b:b/c:c/a is:

Solution:
              Let a,b and c be 3x,4x and 5x respectively.
              a/b:b/c:c/a = 3x/4x : 4x/5x : 5x/3x
                                = 3/4: 4/5: 5/3
                                = 45:48:100.

2. A mixture contains water and oil in the ratio 3:1. If 4 litres of oil is added to the mixture, the ratio becomes 3:2. Find the quantity of water in the given mixture. 

Solution:
               Let the quantity of both be 3x and x respectively.
               3x/(x+4) = 3/2
               6x = 3x+12
               3x = 12
               x = 4.
               The quantity of water in the given solution is 3x = 12 litres.