10% discount and then 20% discount in succession is equivalent to total discount of

• 15%

• 24%

• 30%

• 28%

125.

18 yr ago, the ratio of A's age to B's age was 8 : 13. Their present ratios are 5 : 7. What is the present age of A?

• 70 yr

• 60 yr

• 40 yr

• 50 yr

In certain years a sum of money is doubled itself at  simple interest per annum, then the required time will be

• 16 yr

• 

• 

• 8 yr

If x = 332,  y = 333,   z = 335,  then the value of x³ + y³ + z³ - 3xyz is

• 10000

• 7000

• 9000

• 8000

Walking at the rate of 4 km/h a man covers certain distance in 2 h 45 min. Running at a speed of 16.5 km/h the man will cover the same distance in how many minutes?

• 45

• 50

• 40

• 35

729 mL of a mixture contains milk and water in the ratio 7 : 2. How much more water is to be added to get a new mixture containing milk and water in the ratio 7 : 3?

• 52 mL

• 60 mL

• 71 mL

• 81 mL

What is the Arithmetic mean of the first n natural numbers?

• 

• 

• 2(n+1)

• 

A tap can empty a tank in 30 min. A second tap can empty it in 45 min. If both the taps operate simultaneously, how much time is needed to empty the tank?

• 30 min

• 14 min

• 15 min

• 18 min

The population of a town increases by 5% every year. If the present population is 9261, the population 3 yr ago was

• 8000

• 7500

• 5700

• 6000

The value of 

• 5

• 1

• 0

• 7