The average age of six members of a family is 40 years. If the age of a guest is included, then the average age increases by 12.5%. What is the age (in years) of the guest?

The average salary, per head, of all the workers of an institution is 60. The average salary of 12 officers is 400; the average salary, per head, of the rest is 56. The total number of workers in the institution is -

The average of six numbers is 3.52. The average of two of them is 3.7, while the average of other two is 2.5. What is the average of the remaining two?

The mean weight of 34 students of a school is 42 kg. If the weight of the teacher be included, the mean rises by 400 grams. Find the weight of the teacher (in kg.) 

A man bought 13 articles at 70 each, 15 at 60 each and 12 at 65 each. The average price per article is 

The average monthly salary of all the employees in an industry is Rs. 12,000. The average salary of male employees is Rs. 15,000 and that of female employees is Rs. 8,000. What is the ratio of male employees to female employees?

A batsman scored 87 runs in the 21st match in his career. His average of runs per match increased by 2. What was his average before the 21st match?

The average monthly savings of Shifa for the first 5 months is Rs. 2120, for the next 3 months is Rs. 4260 and for the remaining months of the year is Rs. 3140. Now, the average monthly expenditure for the complete year is Rs. 11000. Find the total income of the year