Aptitude Day 341

Problems on Alligation or Mixture:

1. The cost of type 1 rice is 20 per kg and type 2 rice is 30 per kg. If both type 1 and type 2 are mixed in the ratio of 4: 3, then the price per kg of the mixed variety of rice is:

Solution:

                  20                    30

                                x

                  30-x               x-20

                   (30-x)/(x-20) = 4/3

                   90-3x = 4x-80

                   x = 24.29.

2. In what ratio must a grocer mix 2 varieties of tea worth  40 a kg and 45 a kg so that by selling the mixture at 48 a kg he may gain 8%?

Solution:

                   48/108 *[100] = 400/9

                                           = 44.4.

                   40                    45

                              44.4

                  0.6                    4.4

                 (45-44.4) : (44.4-40) = 0.6 : 4.4 

                                                   = 6 : 44 

                                                   = 3:22.