In how many ways can $12$ distinct pens be divided equally given the following conditions?

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In how many ways can $12$ distinct pens be divided equally

1) among $3$ children.

options

a) 12!/$(4!)^3$ b) 12!/$(4!)^3$ . 3! c) 12!/$(5!)^3$ d) 11!/$(4!)^3$

2) into $3$ parcels.

options

a) 12!/$(4!)^3$ b) 12!/$(4!)^3$ . 3! c) 12!/$(5!)^3$ d) 11!/$(4!)^3$

My approach:

I know here how they to divide them among 3 children by keeping $4$ in each group

HOW i think:

First Select $4$ from $12$,then from remaining again select $4$ and then again do the same thing.

$12C4$ . $8C4$ . $4C4$

=$12!$/$(4!)^3$

Can anyone give me the HINT on How to solve the second part and also I am confused what difference it has with respect to Ist part?

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1 Answer

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Hint for second part:

If you want to divide the pens equally among the 3 children, you can

$\;\;\;$1) divide the pens into 3 equal parcels, and then

$\;\;\;$2) distribute the parcels to the children, which can be done in $3!$ ways.

Therefore the answer to part a) can be obtained by multiplying the answer to part b) by $3!$,

as juantheron's previous answer indicated.

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