averages Model Questions & Answers, Practice Test for ibps rrb po prelims

The age of a man is 4 times that of his son. 5 yrs ago, the man was nine times as old as his son was at that time. What is the present age of the man?

The average weight of a group of 75 girls was calculated as 47 kgs. It was later discovered that the weight of one of the girls was read as 45 kgs., whereas her actual weight was 25 kgs. What is the actual average weight of the group of 75 girls? (Rounded off to two digits after decimal)

The average age of seven boys sitting in a row facing North is 26 yr. If the average age of first three boys is 19 yr and the average age of last three boys is 32 yr. What is the age of the boy who is sitting in middle of the row ?

The average of 30 numbers is 40 and that of other 40 numbers is 30. The average of all the numbers is

Present ages of Rama and Shyama are in the ratio of 4 : 5 respectively. Five years hence the ratio of their ages becomes 5 : 6 respectively. What is Rama’s present age?