13. The data pertaining to the worker C in a factory depicts that he is paid at a rate of ₹ 100 per hour and a week comprises 48 hours for a 6 days’ work. The allowed absence time is 15 minutes per day for maintenance etc. The job card of C indicates, his chargeable time is scattered for 2 different jobs J1-21 hours and J2-24 hours. Any unaccounted time is attributable for power failure. Calculate cost of normal idle time and abnormal idle time.

The value of $\displaystyle N$ in $\displaystyle N! +$\displaystyle \frac{1}{7!} = \frac{1}{8!} is

A person can go from place 'A' to 'B' by 11 different modes of transport but is allowed to return to 'A' by any mode other than the one earlier. The number of different ways in which the entire journey can be completed is:

If a man travels from place A to B in 10 ways then by how many ways can he come back by another train?

If $\displaystyle \frac{n!}{10(n-1)!} = \frac{(n-1)!}{(n-3)!}$ find 'n'.

Which of the following is a correct statement.

$\displaystyle ^nP_3 = 2 \cdot ^nP_2$. Find $\displaystyle n$.