Quantitative Aptitude - Arithmetic Ability Questions

Two valves P and B can fill a sump in 37.5 minutes and 45 minutes respectively. Both valves are opened. The sump will be filled in just 30 minutes, if valve B is turned off after

What is the average of first 19 odd numbers?

The traffic lights at four different road crossings change after every 15 sec, 18 sec, 27 sec and 30 sec respectively. If they all change simultaneously at 6:10:00 hours, then at what time will they again change simultaneously?

The average of 17 results is 60. If the average of first 9 results is 57 and that of the last 9 results is 65, then what will be the value of 9th result?

If the shopkeeper sells an item at Rs 1000 which is marked as Rs 1250, then what is the discount he is offering?

Calculate the principal if an amount of Rs. 441 is received on compound interest at the rate of 5% per annum after 2 years.

If  a+1/a = 3, then a3+1a3?

Find the value of x if 0.08x + 0.04y = 10 and 0.2(x-1) + 0.4y = 24.8