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# How to do this??????

Three children, each accompanied by a guardian,seek admission in a school. The principal wants to interview all the 6 one after the other subject to the condition that no child is interviewed before its guardian. In how many ways can this be done? (please give a detailed answer)

Note by Rajath Krishna R
4 years, 3 months ago

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Your problem is the same of anagramming the letters AABBCC:

$$\frac {6!} {2! 2! 2!}$$

Take a children and his guardian as equal things. Once they are ordered, the guardian is always the first occurrence of the couple.

- 4 years, 3 months ago