A trader buys a hand watch for Rs.450 and determines its marked price in such a way that even after allowing a discount of 10% on that watch, he makes a profit of 20%. What is the marked price of the watch?

Answer the following questions

There are three numbers in such a way that the average of the first and second numbers is 68 more than the average of the second and third number. Find the difference between first and the third number.

Which of the f ollowing numbers will replace the question mark (?) in the given series?
 15, 27, 12, ?, 9, 33

Three pipes A, B can fill the tank in 12, 20 hrs respectively and C can empty the tank in 30 hours. If the pipes are opened alternatively for 1 hour starting with A and drain pipe is kept open all the time. How much time will it take to fill the tank.

Direction: What value will come in place of the question mark (?) in the following question?

230, 204, 187, 177, 172, ?

The average of 11 numbers is 7. If each number is doubled, what will be the new average of the numbers?

 In a family, the average age of a father and a mother is 35 years. The average age of the father, mother and their only son is 27 years. What is the age of the son? 

A man can row upstream at 12 km/hr and dowstream at 18 km/hr. The man's rowing speed in still water is: