Answer
Out of all months of the year there are 4 months don't have letter 'R' in them these are [May,June,July,August]
The ven diagram is given bellow with discription
Work Step by Step
set of months of the year=
{January, February, March, April, May, June, July, August, September, October, November, December}
set of months don't having letter 'R' in their name={May, June, July, August}
Set of all months will treated as the "Universal set" and the set having letter 'R' in them are treated as the "Subset of the Universal set",
as we know that in venn diagram the the subset is represented inside the universal set as shown in the figure below.