$A$ lot consists of $48$ mobile phones of which $42$ are good,$3$ have only minor defects,and $3$ have major defects. Varnika will buy a phone if it is good,but the trader will only buy a mobile if it has no major defect. One phone is selected at random from the lot. What is the probability that it is
$(i)$ acceptable to Varnika?
$(ii)$ acceptable to the trader?

(N/A) Given,total number of mobile phones $n(S) = 48$.
$(i)$ Let $E_{1}$ be the event that Varnika will buy a mobile phone.
Varnika buys only if it is a good mobile.
Therefore,$n(E_{1}) = 42$.
$P(E_{1}) = \frac{n(E_{1})}{n(S)} = \frac{42}{48} = \frac{7}{8}$.
$(ii)$ Let $E_{2}$ be the event that the trader will buy a mobile phone.
The trader will buy only if it has no major defects.
This means the trader will buy the $42$ good phones and the $3$ phones with minor defects.
Therefore,$n(E_{2}) = 42 + 3 = 45$.
$P(E_{2}) = \frac{n(E_{2})}{n(S)} = \frac{45}{48} = \frac{15}{16}$.