Direction : What should come in place of the question (?) in the following question.

$$3{5\over7}× 4{5\over6} + ? =23{3\over4}$$

If 2A = 3B = 7C = 42, then what is the value of A × B ÷ C?

Direction : What should come in place of the question (?) in the following question.

35% of 430 + ? % of 360 = 276.5

If the 5 digit number 538xy is divisible by 3, 7 and 11, then the value of (x² +y²)  is:

1332.89+171.928+17.01 +?²=1690.87

A number whose one - fifth part increased by 4 is equal to its one - fourth part diminished by 10 is: 

There are four numbers in a set. The mean of the three smallest numbers is 9, whereas the mean of the three largest ones is 11. What is the range of the data set? 

Find the mean of first Five Prime Numbers.