The average of 8 readings is 24.3, out of which the average of first two is 18.5 and that of next three is 21.2. If the sixth reading is 3 less than seventh and 8 less than eight, what is the sixth reading? 

What approximate value should come in place of the question mark(?) in the following question?
5223÷36×0.93=?

The average of nine numbers in M and the average of three of these is P. If the average of remaining numbers is N, then

A trader sold an article at profit of 20%. Had he bought that article at 60% less price and sold it at Rs 90 less, then he would have gained 50%. What is the value (in Rs) of cost price? 

Diameter of a cycle wheel is 14 cm. A cyclist takes 30 minutes to reach a destination at a speed at 11 km/h. How many revolutions will the wheel make during the journey?

120 men consume 720 kg of rice in 30 days. In how many days can 90 men consume 270 kg?

If a clock strikes 12 in 33 seconds, it will strike 6 in how many seconds?