For the following questions answer them individually
Given $$A =2^{65}$$ and $$B = (2^{64} + 2^{63} + 2^{62} + ... + 2^{0})$$, which of the following is true?
A bag contains 4 blue, 5 white and 6 green balls. Two balls are drawn at random. What is the probability that one ball is white?
Two pipes P and Q can fill a tank in 20hrs and 25hrs respectively while a third pipe R can empty the tank in 30hrs. If all the pipes are opened together for 10hrs and then pipe R is closed then in what time the tank can be filled.
If there are Rs 495 in a bag in denominations of one-rupee, 50 paisa and 25 paisa coins, which are in the ratio 1 : 8 : 16. How many 50 paisa coins are there in the bag?
One-fifth of a number is equal to $$\dfrac{5}{8}th$$ of another number. If 35 is added to the first number, it becomes four times of the second number. Find the second number.