Quantitative Aptitude - Arithmetic Ability Questions

If the mean of m observations out of n observations is n and the mean of remaining observations is m, then what is the mean of all n observations?

Pipes A and B can fill a cistern in 15 hours together. But ifthese pipes operate separately A takes 40 hours less than Bto fill the tank. In how many hours the pipe A will fill thecistern working alone?

X starts a business with Rs 80000. After 6 months Y joins X with Rs 100000. After 2 years, what will be the ratio of profit of X and Y?

80 litre mixture of milk and water contains 10% milk. How much milk (in litres) must be added to make water percentage in the mixture as 80%?

How many numbers are there from 700 to 950 (including both) which are neither divisible by 3 nor by 7?

In the following question, select the odd letter/letters from the given alternatives.

In how many different ways can the letters of the word 'RITUAL' be arranged?

The LCM of 16, 24, 36, 52 and 54 is?