Exams

Contra-entry is the entry which effected the both sides in cash book.

It is occured in three times, i.e.,

1.Cash deposited in to bank,

2.Cash withdrawn from the bank for office use, and

3.Receivable cheque deposited in to the bank in another day.

Let the number be 'x'.

x+x22 = 11x
x2= 22x
=> x = 22.

The distance to be covered = Sum of their lengths = 200 + 300 = 500 m.

Relative speed = 72 -36 = 36 kmph = 36 x 5/18 = 10 mps.

Time required = d/s = 500/10 = 50 sec.

A Sound wave needs a medium for propogation. Hence, Sound cannot travel through a vacuum.

A vacuum is an area without any air, like space. So sound cannot travel through space because there is no matter for the vibrations to work in.

Here by observing the figure, 

we can complete the above incomplete cube with 2 cubes in 2 rows and 2 columns

=> 2 x 4 = 8.

Hence, with 8 small cubes we can complete the cube.