Quantitative Aptitude - Arithmetic Ability Questions

If a - b = -6 and a2 + b2 = 44, then ab is

If the population of a town increases by 25% in the first year and increases by 36% in the second year, then what is the average rate (in percentage)of increase in the population?

A bank offers 20% compound interest per half year. A customer deposits Rs 6000 each on 1st January and 1st July of a year. At the end of the year, the amount he would have gained by way of interest is

If cosαcosβ=m and cosαsinβ=n,then the value of m2+n2 cos2β is

10 persons can do a job in X days. If 20 persons with twice the efficiency can do the same job in 5 days, then find the value of X?

If the 8 digit number 136P5785 is divisible by 15, then find the least possible value of P?

A man covers a total distance of 100 km on bicycle. For the first 2 hours, the speed was 20 km/hr and for the rest of the journey, it came down to 10 km/hr. The average speed will be

The average of 21 numbers is 12. The average of the first 11 numbers is 9 and the average of the last 11 numbers is 15. What is the value of the middle number?