If today is Sunday, July 4, and next year is not a leap year, what day of the week will July 4 be on next year?

July 4th of the next year will be on a Monday.

Step-by-step explanation:

We have the following "circular" sequence of days:

{Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday}

When it is a leap year, days jump two positions.

For example, Wednesday to Friday, Friday to Sunday.

For example, 2020 is a leap year. In 2019, September 8 was on a Sunday. This year is going to be on a Tuesday.

When it is not a leap year, days jump one position

So Saturday to Sunday, Sunday to Monday ...

2019 was not a leap year. September 8, 2018 was a Saturday. In 2019, it was a sunday.

So

July 4th of the next year will be on a Monday.