Question

In a non-leap year, the probability of getting $53$ Sundays or $53$ Tuesdays or $53$ Thursdays is

• A. $\frac{1}{7}$
• B. $\frac{2}{7}$
• C. $\frac{3}{7}$
• D. $\frac{4}{7}$

Answer 1

Answer: (C)

Days in a non leap year $= 365$
So there are $52$ weeks and one day.
This one day may be anyone in sample space [Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday]
So, $P$ ($53$ Sundays or $53$ Tuesdays or $53$ Thursdays)
$=\frac{1}{7}+\frac{1}{7}+\frac{1}{7} = \frac{3}{7}$.