Question

t​ Technodynamics, Inc., a​ randomly-selected hiring committee of 3 people is formed from a group of 4 employees in marketing and 7 employees in management. ​a) Find the probability that the committee has exactly 2 employees from marketing. ​b) Find the probability that the committee has at least one employee from marketing. ​c) Find the probability that the committee has at most one employee from management.

Answer 1

Answer: a) 0.25, b) 0.78, c) 0.71

Step-by-step explanation:

Since we have given that

Number of employees in marketing = 4

Number of employees in management = 7

We need to hire committee of 3 people.

​a) Find the probability that the committee has exactly 2 employees from marketing.

So, Probability becomes

$\dfrac{^4C_2\times ^7C_1}{^{11}C_3}\\\\=\dfrac{42}{165}\\\\=0.25$

​b) Find the probability that the committee has at least one employee from marketing.

$P(x\geq 1)=1-P(x=0)\\\\P(x\geq 1)=1-\dfrac{^7C_3}{^{11}C_3}=1-0.212=0.78$

c) Find the probability that the committee has at most one employee from management.

$P(x\leq 1)=P(x=0)+P(x=1)\\\\P(x\leq 1)=\dfrac{^7C_3}{^{11}C_3}+\dfrac{^7C_2\times ^4C_1}{^{11}C_3}\\\\P(x\leq 1)=0.21+0.50=0.71$

Hence, a) 0.25, b) 0.78, c) 0.71