Question

Since taking office, Joe Biden has spent 301 days — 40% of his presidency — on vacation.

Answer 1

No other source claims that Joe Biden took exactly 301 days on vacation. Some other untrustworthy cites like newyorkpost and dailymail claim that Joe Biden has taken 40% of his presidency on vacation. They do use Mark Knoller who is a former correspondent with CBS as a source for their tally counts. From my research it seems that Knoller has been tallying presidents based on there days they travel, golf, etc all on twitter and he is credible.

What makes this tweet a clear lie is the CNN article written by Kate Bennett, a reporter and journalist who claims that Joe Biden spent 40% of his presidency in Delaware working. 

Just because he is not in the White House does not mean he is not working!

In this article she also uses Mark Knoller as her source for the days she lists Biden has been in Delaware, which is 174. With this article being written last year I believe the number could have changed. She also states that while he is in Delaware he is still working and not on vacation. Given that the number of 301 is also not supported in any other source I would claim this tweet to be false.

Here is the CNN article that will help you understand why the tweet is not true

https://www.cnn.com/2022/10/17/politics/joe-biden-presidency-delaware-work-from-home/index.html

Answer 2

I found that this is true according to the The New york post: "President Biden is taking heat for spending 40% of his days in office “on vacation” after he was away from the White House for two-thirds of August.

Biden’s weekend jaunts and vacations spanned 234 days — with seven in 10 of them spent at his homes in Wilmington and Rehoboth Beach, Delaware — out of 589 days in office."

-Biden hit for spending 40% of his time 'on vacation' (nypost.com)

Since taking office, Joe Biden has spent 301 days — 40% of his presidency — on vacation.