The angle between the minute hand and the hour hand of a clock, when the time is 8.30

Rs. 1581 is divided among A, B and C in the ratio 10 : 15 : 6. What is the share of B?

The sum of four consecutive counting numbers is 154. Find the smallest number:

A clock shows the time as 6 a.m. If the minute hand gains 2 minutes every hour, how many minutes will the clock gain by 9 p.m.?

Judge : Justice : Censor: ?

All natural numbers and 0 are called the _______ numbers.