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From the employees of a company, $5$ persons are selected to represent them in the managing committee of the company. Particulars of five persons are as follows :
| S.No. | Name | Sex | Age in years |
| $1.$ | Harish | $M$ | $30$ |
| $2.$ | Rohan | $M$ | $33$ |
| $3.$ | Sheetal | $F$ | $46$ |
| $4.$ | Alis | $F$ | $28$ |
| $5.$ | Salim | $M$ | $41$ |
A person is selected at random from this group to act as a spokesperson. What is the probability that the spokesperson will be either male or over $35$ years?
$\frac{4}{5}$
$\frac{4}{5}$
$\frac{4}{5}$
$\frac{4}{5}$
Solution
Let $E$ be the event in which the spokesperson will be a male and $F$ be the event in which the spokesperson will be over $35$ years of age.
Accordingly, $P ( E )=\frac{3}{5}$ and $P ( F )=\frac{2}{5}$
since there is only one male who is over $35$ years of age,
$P ( E \cap F)=\frac{1}{5}$
We know that $P ( E \cup F)= P ( E )+ P ( F )- P ( E \cap F )$
$\therefore P ( E \cup F )=\frac{3}{5}+\frac{2}{5}-\frac{1}{5}=\frac{4}{5}$
Thus, the probability that the spokesperson will either be a male or over $35$ years of age is $\frac{4}{5}$.
