Given:
Total no of pens is 8.
No of pens that works =4
No of pens that don't work = 4
[tex]\text{Probability }of\text{ selecting 3 pens }from\text{ the drawer=}\frac{3}{8}[/tex][tex]\text{Probability of selecting }a\text{ pen thta don't work=}\frac{4}{8}[/tex][tex]\begin{gathered} \text{Probability of getting 3 pens from a drawer }and\text{ don't} \\ \text{ end up with a pen }that\text{ work is } \end{gathered}[/tex][tex]=\frac{3}{8}\times\frac{4}{8}[/tex][tex]=\frac{3}{16}[/tex][tex]=0.1875[/tex]
