Quantitative Aptitude - Arithmetic Ability Questions

Solve the following : -1/4 { -45 - (-96) / (-32)} = ?

Find the square root of 15625.

Excluding stoppages, the speed of a train is 120 kmph and including stoppages, it is 50 kmph. For how many minutes does the train stop per hour?

The sum of the present ages of a father and his son is 126 years. 8 years ago their respective ages were in the ratio of 7 : 4. After 7 years what will be the ratio of ages of father and son?

The ratio of present ages of P and Q is 7:9. Before 10 years the ratio of their ages was 5:7. What is Q's present age (in years)?

Painter A can paint a house in 40 days and Painter B can do it in 60 days. With help of C, they did the job in 20 days only. Then, C alone can do the job in

A and B together can do a piece of work in 9 days. If A does thrice the work of B in a given time, the time A alone will take to finish the work is

Oil equal to 20% of the weight of ground nut is extracted in a mill. The matter left after extraction is sold as cattle feed at the rate of Rs 12.5/kg. The groundnuts are bought at Rs 20/kg. The processing cost is Rs 5/kg. At what price (Rs per kg) should the oil be sold to earn 20% profit on total costs (Total cost = Cost of groundnuts and Processing costs)?