A sum of Rs.1600 gives a simple interest of Rs.252 in 2 years and 3 months. The rate of interest per annum is 

A person invested 1100 in a company at compound interest compounded semi-annually. He received 1331 after one year. The rate of interest per annum is 

If 1.5a=0.04 b then find out the value of $$ {b-a\over b+a}$$.

A fan s listed at ₹ 150 with a discount of 20%. What additional discount must be offered to the customer to bring the net price to ₹ 108

The sum of two positive numbers is 20% of the sum of their squares and 25% of the difference of their squares. If the numbers are x and y then, is equal to

The average of 8 readings is 24.3, out of which the average of the first two is 18.5 and that of next three is 21.2. If the sixth reading is 3 less than seventh and 8 less than eight, what is the sixth reading? 

A certain sum of Rs.4200 becomes Rs5523 at 11% p.a simple interest in a certain time. What is the simple interest on the sum of Rs. 4800 at the same rate and in same time period?

Pipes A and B can fill a tank in 12 minutes and 15 minutes, respectively. The tank when full can be emptied by pipe C in x minutes. When all the three pipes are opened simultaneously, the tank is full in 10 minutes. The value of x is: