Directions : What will come in the place of the question mark (?) in the following number series?

60.75, 40.5, 27, 18, 12, ?

Mr. Dev sold a bus for Rs. 2210 with a loss of 15 %. At what price should the bus be sold to get a profit ot 15 %?

A double bed is marked at  ₹ 7,5000. The shopkeeper allows successive discounts of 8 %, 5 % and 2 % on it. What is the net selling price? 

The distance between the tops of two building 38 metres and 58 metres and high is 52 metres. What will be the distance (in metres) between two building?

Tank is normally filled in 8 hours but takes 2 hours longer to fill because of a leak in its bottom. If the cistern is full, in how many hours will the leak empty it? 

Speed of current is 10% of speed of boat in still water and the time taken by the boat to cover X km in downstream is 100% more than time taken by the boat to cover (X-45) km in upstream. Find the value of X?

The length of a rectangle is 6 cm more than its width and its perimeter is 100 cm. If the area of this rectangle is closest to the area of a circle, then what is the circumference of that circle?

Pranav rows upstream a distance of 56km in 8 hours and rows downstream a distance of 75 km in 3 hours. How much time he will take to row a distance of 44.8 km in still water?