If x⁴+2x³+ax²+bx+9 is a perfect square where a and b are positive real numbers, then the value of a and b 

Pipes A and B can fill a tank in 43.2 minutes and 108 minutes, respectively. Pipe C can empty it at 3 litres/minute. When all the three pipes are opened together, they fill the tank in 54 minutes. The capacity (in litres) of the tank is:

If P is 15 years old now and Q will be 26 years old after 6 years, what is the ratio of their percentages? 

A train of length 200 m crosses a platform of which is 50 m more than train in 18 sec. Find the speed of train. 

Two buses start at the same time from Delhi and Agra, which are 300 km. apart, towards each other. After what time will they cross each other if their speeds are 38 km per hour and 37 km per hour?

A copper wire is bent in the shape of a square of area 81 cm². If the same wire is bent in the form of a semicircle, the radius (in cm) of the semicircle is (take π=22/7 ) 

If C.P of 20 tables is equal to the S.P of 25 tables. Find the loss percentage.

A and B together have ₹ 158. C has ₹101 less than what A and B together have, and B has ₹ 23 more than C. The amount of A is: