Aptitude Day 101

Ratio and Proportion:

1. The speeds of 3 cars are in the ratio 3:5:9. The ratio between the time taken by them to travel the same distance is:

Solution:

                Speed = Distance/ Time

                The Time ratio is  1/3: 1/5: 1/9

                The required ratio is 15: 9: 5

2. In a college, the ratio of the girls and boys is 4:7. If there are 420 boys, the total number of students in the college is:

Solution:

               The Number of boys = 420.

               7x = 420

               x = 60.

               The total number of students = 4x+7x

                                                              = 11x =11(60)

                                                              = 660.