Hi
chetan2u,
I think that solves my query, thank you so much.
So do you think this is the right thought flow to identify which formula to use (sorry if I am bothering with too many questions, but my exam is 11 days away, and so far P&C is my biggest weakness
)
1. identify whether it is an 'arrangement' question or 'select question'
2. if it is an 'arrangement' question, we have to use the Permutation formula, or the n! formula (divide by a! where a=similar elements)
3. if it is a 'choose' / 'select' question then first identify whether it matters how we choose. If order matters, i.e. abc is not the same as cab then select use combination formula. If order doesn't matter then use the permutation formula
Is there anything I am missing?