Quantitative Aptitude - Arithmetic Ability Questions

What is the value of cos [(180 – θ)/2] cos [(180 – 9θ)/2] + sin [(180 – 3θ)/2] sin [(180 – 13θ)/2]?

A shopkeeper, sold cocoa seeds at the rate Rs 1,230 a kg and bears a loss of 5%. Now if he decides to sell it at Rs 1,353 per kg, what will be the result?

A can do a piece of work in 10 days and B in 12 days. With help of C, they finish the work in 4 days. In how many days C alone can do the same work?

8 men can complete a work in 16 days. 16 women can complete the same work in 24 days. In how many days can 4 men and 8 women complete the same work?

A card is drawn from a pack of 52 cards. What is the probability that either card is black or a king? 

If 35% of A's income is equal to 25% of B's income, then the ratio of A's income to B's income is

A box contains 5 green, 4 yellow and 3 white marbles. Threemarbles are drawn at random. What is the probability thatthey are not of the same colour ?

In a class of 100 students, the average weight is 30 kg. If the average weight of the girls is 24 kg and that of the boys is 32 kg, then what is the number of girls in the class?