probability questions

[cuttiedentist]

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im really confused about these probability math questions. i dont know when to use which formula. for example on destroyer QR number 20 and 27, they look the same kind of question to me and the explanations are also the same. but i dont understand why two kind of formulas were used.
i really appreciate if someone can help me with this
pleaseeeeeeee

 

[Decan]

20 is a permutation (order does matter) whereas 27 is a combinatin (order does not matter). In 20, 8 horses can finish are race in only 3 ways...in 27, it doesnt matter which balloons are used to make the 3 balloon combo.

Does that make sense?

 

[cuttiedentist]

20 is a permutation (order does matter) whereas 27 is a combinatin (order does not matter). In 20, 8 horses can finish are race in only 3 ways...in 27, it doesnt matter which balloons are used to make the 3 balloon combo.

Does that make sense?

yes it does thanks, but im still a little confused. also on question number 86 it used the same formula as in number 20. here in this question dors the order of colors matter?

 

[cuttiedentist]

and also i dont understand the difference between question 27 and 89. they are basically the same questions but why are they solved in different ways?
sorry im so bad in probabilities

 

[z3u2]

why don't you post the question up?

 

[sacjumpman]

and also i dont understand the difference between question 27 and 89. they are basically the same questions but why are they solved in different ways?
sorry im so bad in probabilities

I wiki searched for "permutation" and "combination" and it helped explain it to me.

I was having the same trouble getting the difference between those two.