Question

The probability that the ${13}^{th}$ day of a randomly chosen month is a second Saturday, is

• A. $\frac{1}{7}$
• B. $\frac{1}{12}$
• C. $\frac{1}{84}$
• D. $\frac{19}{84}$

Answer 1

The correct option is C $\frac{1}{84}$

Probability of selecting one month out of
$12=\frac{1}{12}$
Since, Saturday is in a week (i.e., 7 days)
Probability of Saturday in a week =$\frac{1}{7}$
Hence, probability of 13th day of a randomly chosen month is a second Saturday
$=\frac{1}{12}\times \frac{1}{7}=\frac{1}{84}$