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

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

In a group of students, 70 % can speak English and 65 % can speak Hindi. If 27 % of the students can speak none of the two languages, then what percent of the group can speak both the languages? 

A tap drips at a rate of one drop/sec. 600 drops make 100ml. The number of litres wasted in 300 days is: 

The smallest perfect square divisible by each of 6, 12 and 18 is : 

The average speed of a train is 3 times the average speed of car. The car covers a distance of 520 km in 8 hours. How much distance will the train cover in 13 hours?

Either 8 men or 17 women can paint a house in 33 days. The number of days required to paint three such houses by 12 men and 24 women working at the same rate is: