A cistern can be filled by two pipes A and B in 10 and 15 hours respectively and is then emptied by a tap in 8 hours. If all the taps are opened, the cistern will be fill in:

A locomotive engine, without any wagons
attached to it, can go at a speed of 40 km/hr. Its speed is diminished by a quantity that varies proportionally as the square root of the number of wagons attached. With 16 wagons, its speed is 28 km/hr. The

If 33 untrained labourers can do a work in 15 days of 12 hr. each, how many trained labourers can do 50% more work in 11 days of 9 hr each ? (It may be assumed that it takes 2 trained labourers to do the work of 5 untrained labourers)

Which of the following fractions is less than 7/8 and greater than 1/3 ?

892.7 - 573.07 - 95.007 = ?

Which is the closest approximation to the product 0.3333 x 0.25 x 0.499 x 0.125 x 24 ?

Find the value of X :
0.009/X = 0.01

The least among the following is:

In the following expression, there are two missing digits: * and #. Find the value of *.
1*5#4 / 148 = 78

What is the value of (-5)(4)(2)(-1/2)(3/4) ?