The average age of a family of 6 members is 22 years. If the age of the youngest member be 7 years the average of the family at the birth of the youngest member was -

Mr. Girdhar spends 50 % of his monthly income on household items and out of the remaining he spends 50% on transport 25% on entertainment, 10% on sports and remaining amount of Rs.900 is saved. What is Mr.Giridhar's monthly income? 

What is the value of positive square root of $$\ 14+ 6\sqrt{5}\ $$?

A used car dealer sells a car for Rs 7.6 lakhs and makes some loss. If he had sold if for Rs.9.2 lakhs his profit would been thrice of his loss. What was the cost price of the car (in Rs. Lakhs)? 

Sudhir and Shyam can do a work in 12 days, while Shyam alone can complete it in 30 days. In how many days can Sudhir complete that work alone?

Ratio of the principal and the amount after 5 year is 10:12. Then the rate of interest per annum is 

Ravi purchases 90 pens and sells 40 pens at a gain of 10% and 50 pens at a gain of 20%. Had he sold all of them at a uniform profit of 15% he would have got Rs. 40 less. Find the cost price of each pen.