A wall clock strikes the bell once at 1 o' clock, 2 times at 2 o' clock, 3 times at 3 o' clock and so on. How many times will it strike in a particular day. Find the standard deviation of the number of strikes the bell make a day.

If a clock strickes once at 1 o'clock, twice at 2o'clock, thrice at 3 o'clock and so on. How many times will it strikes in day?

What is the angle between two hands of a clock when the time in the clock is (a) 9’O clock (b) 6’O clock (c) 7:00 PM

Length of the shadow of a 15 meter high pole is 5sqrt3 meters at 8 O'clock in the moming. Then, what is the angle of elevation ofthe Sun rays with the ground at the time?

Find the number of all possible matrices of order 3xx3 with each entry 0 or 1. How many of these are symmetric ?

If A is a 2times3 matrix and B is 3times4 matrix, how many columns does AB have

The pendulum of certain clock has time period 2.04 s. How fast or slow does the clock run during 24 hours?

150 workers were engaged to finish a piece of work in a certain number of days. Four workers dropped from the work on the second day. Four workers dropped on third day and so on. It took 8 more days to finish the work. Find the number of days in which the work was completed. [Let the no.of days to finish the work is 'r' then 150 x = (x+8)/2 [2 xx 150 + (x+8-1)(-4)]