Question

7. If there are six periods in each working day of a school, in how many ways can one arrange t subjects such that each subject is allowed at least one period
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Answer 1

Step-by-step explanation:

5 subjects can be arranged in 6 periods in 6

P

5

ways.

Any of the 5 subjects can be organized in the remaining period (5

C

1

ways).

Two subjects are alike in each of the arrangement. So we need to divide by 2! to avoid overcounting.

Total number of arrangements =

2!

6

P

5

×5

C

1

=1800