Find the standard deviation of the following data (rounded off to two decimal places). 5, 3, 4, 7 

A woman buys a watch for Rs. 4,000 and sells it at a loss of 13%. What is the selling price of the watch?

Two cars travel from city A to city B at a speed of 36 and  48 km/hr respectively. If one  car takes 3 hours lesser time  than the other car for the journey, then  the distance between City A and  City B is

The average of the largest and smallest 3 digit numbers formed by 0, 2 and 4 would be 

  The value of $${{1}\over 1+\sqrt { 2} + \sqrt { 3}}+{{1}\over 1-\sqrt { 2} + \sqrt { 3}} $$ is

According to an instruction a mixture of colour and Turpentine containing half part of each is perfect for painting a wall. A painter is provided a mixture, 3 parts of which are colour and 5 parts are Turpentine. How much of the mixture drawn off and replaced with colour so that the mixture becomes perfect?

The table given below shows the information about bats manufactured by 6 different companies. Each company manufactures only plastic and wooden bats. Each company labels these bats as Brand A or Brand B. The table shows the number of plastic bats as a percentage of total bats manufactured by each company. It also shows the ratio of wooden bats labelled A and B. Each company manufactured a total 550000 bats.

Taking all 6 companies together, how many wooden bats of Brand A have been produced?

Find the greatest number 23a68b, which is divisible by 3 but NOT divisible by 9.