Cez005 wrote:

okay wrote:

Whether or not order matters will be determined on a case-by-case basis. If you are selecting 3 people for a team (i.e. you're either on the team or not), order doesn't matter. If you are selecting 3 people for 3 different positions on the team (e.g. president, VP, secretary), order does matter.

Thanks for your reply but I'm talking about order with regard to probability and not just general order.

Hi Cez,

Your understanding is apt. What 'Okay' gave is an example for the rule you wrote.

A general tip that I would like to give you is that whenever you are caught in this dilemma, try to ask yourself, whether it is the case of "selection" or "arrangement". Generally, order does not matter in "selection" and it does so in "selections".

Examples:

1. A team of five is selected from a group of four boys and seven girls. What is the probability that no boy is selected?

A case of selection and hence, the order shall not matter (in numerator as well as denominator).

2. Letters of the word COMPUTER are shuffled. What is the probability that C comes before both O and U?

A case of arrangement and hence, the order shall matter (in numerator as well as denominator).

Hope that helps!

All the best!

Maxximus

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