What approximate value should come in the place of question mark (?) in the following question?

1/3 of 785.99 – 11/8 of 1031.99 = ? – 13/4 of 527.98

The difference between the greatest and least prime numbers which are less than 100 is:

$${\sqrt{4×?}}={160\over 10}$$

How many kilometers will a cyclist cover in 2 hours 20 minutes with a speed of 5 meters per second?

The diagonal of a square A is (a+b). The diagonal of a square whose area is twice the area of square A, is

What is the average of the first 13 odd numbers?

Let ABC be an equilateral triangle and AX, BY, CZ be the altitudes. Then the right statement out of the four given responses is

The ratio of the cost price and selling price of an article is 10 : 11. The gain per cent is: