Ques:- Five years ago, the total of the ages of a father and his son was 40 years. The ratio of their present ages is 4 : 1. What is the present age of the father?
A. 20 years
B. 30 years
C. 40 years
D. 50 years
Ques:- There is a leak in the bottom of a cistern. When the cisternis thoroughly repaired, it would be filled in 3 ? hours. It now takes half an hour longer. If the cistern is full, howlong will the leak take to empty the cistern?
A. 24 hours
B. 28 hours
C. 21 hours
D. 27 hours
E. None of these