averages Model Questions & Answers, Practice Test for ssc cgl tier 1

The average of five numbers is 281. The average of the first two numbers is 280 and the average of the last two numbers is 178.5. What is the third number ?

The average weight of 45 students in a class was calculated as 36 kg. It was later found that the weight of two students in the class was wrongly calculated. The actual weight of one of the boys in the class was 32 kg. but it was calculated as 34 kg, and the weight of another boy in the class was 45 kg. whereas it was calculated as boy in the class was 45 kg. whereas it was calculated as 40 kg. What is the actual average weight of the 45 students in the class ? (Rounded off to two digits after decimal)

The present ages of three persons are in proportions 4 : 7 : 9. Eight years ago, the sum of their ages was 56. Find their present ages (in years).

A person invested part of Rs. 45000 at 4% and the rest at 6%. If his annual income from both are equal, then what is the average rate of interest?

The average weight of students in a class is 43 kg. Four new students are admitted to the class whose weights are 42 kg, 36.5 kg, 39 kg and 42.5 kg respectively. Now the average weight–of the students of the class is 42.5 kg, The number of students in the beginning was