Four acts are scheduled to perform in a variety show. How many different ways are there to schedule their appearances?
Hi! What have you tried so far?
(Also, welcome to OpenStudy!)
I tried to work it out
That's good. Do you have any ideas at all, or are you completely stuck?
(Being completely stuck is fine, by the way!) :)
completely stuck
Okay! Let's imagine that we're scheduling the acts, one slot at a time. We might start by deciding who's first, then after that we could decide who's second, then who's third, and then who's last.
How many options do we have, when deciding who's first?
four
Great!
Now imagine we've decided who's first. How many options do we have left, when deciding who's second?
three
Well done :) So how about third and fourth?
? what do you mean
Well, if you imagine that we've chosen the first and second acts, how many options are left when deciding who's third?
two options
Great! And then how many options are left for the fourth act?
one
Well done! That means we had 4 options at the beginning, and then in each case we got 3 options, and then 2 options, and then 1 option. How do you think we might combine them to figure out our overall number of options?
(Clue: we don't want to add them up!)
4 x 3 x 2 x1
Excellent, well done!
so that is my answer? after I times
Yes, that's the answer!
ok thank you for your help
you're most welcome!
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