A teacher has to distribute 15 pens among 5 of his students such that student A gets at least 3 and at most 6 pens.In how many ways can this be done ?
\(\large \color{black}{\begin{align} & \normalsize \text{A teacher has to distribute 15 pens among 5 of his students such}\hspace{.33em}\\~\\ & \normalsize \text{that student A gets at least 3 and at most 6 pens.In how many }\hspace{.33em}\\~\\ & \normalsize \text{ ways can this be done ?}\hspace{.33em}\\~\\ & a.)\ 495 \hspace{.33em}\\~\\ & b.)\ 77 \hspace{.33em}\\~\\ & c.)\ 417 \hspace{.33em}\\~\\ & d.)\ 435 \hspace{.33em}\\~\\ \end{align}}\)
only student A gets atleast 3 to 6 pens necessarily
lets do 4 cases then Student A 3 4 5 6
when student A gets 3 pens we have 12 pens to distribute among 4 students
12C4=495
u cant just do that
why are you doing 12 choose 4
cuz i left with 4 students and 12 pens
wait umm from your previous questions, when they ask questions like this does that mean the pens are distinguishable or not?
i think pens are similar/identical
okay phew that makes it a lot simpler
so we have 12 pens and 4 students think about it like stars and bars question
15C3
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