Combination Question: 8 Things Divided in Groups of 5 & 3

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To determine the number of ways to divide 8 different items into groups of 5 and 3, the correct approach involves using combinations. The calculation can be simplified to 8C5, as selecting 5 items automatically determines the remaining 3. Alternatively, one can consider arranging the items in a sequence of 5 "0"s and 3 "1"s, representing the two groups. This method also leads to the same result, confirming the combinatorial approach. The discussion emphasizes understanding the relationship between group selection and arrangement.
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Homework Statement




In how many ways can 8 different things be divided into groups of 5 and 3.


Homework Equations





The Attempt at a Solution



I thought it be just be 8C5 X 8C3

but also might it be 8C5 x 3C3 since if you take 5 you only have 3 left to select from?
 
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lionely said:

Homework Statement




In how many ways can 8 different things be divided into groups of 5 and 3.


Homework Equations





The Attempt at a Solution



I thought it be just be 8C5 X 8C3

but also might it be 8C5 x 3C3 since if you take 5 you only have 3 left to select from?

If you pick the three for one group you automatically leave 5 for the other group.
 
Another way to look at this is to arrange the 8 items in a row, then label those to go into the first group "0" and those to go into the second group "1". How many different way are there to order 5 "0"s and 3 "1"s?
 
Thank you
 
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