# Some months have 31 days and some have 30. How many have 28?

Source: https://silverapuzzles.com/riddles/some-months-have-31-days-and-some-have-30-how-many-have-28

A calendar riddle built to trigger one word: February. The question is really about how you read the word “have”.

**Answer:** All of them.

Every month has at least 28 days.

Hint: Not just February.

## How to think about it

1. The instinctive reply is one month, February, because it is the only month with exactly 28 days in a common year.
2. Reread the question. It asks how many months have 28 days, not how many have only 28.
3. A month with 31 days certainly has 28 of them, and so does a month with 30.
4. Every month of the year has at least 28 days, so the answer is all twelve.

## Why “All of them” is the answer

Each of the twelve months contains a 28th day, so every month “has 28 days” even though most of them have more. The riddle sets a trap by mentioning 31 and 30 first, which makes you treat 28 as a category instead of a minimum. February is special only because it has nothing beyond the 28th in a common year.

## Common wrong answers

- **One.** February is the only month with exactly 28 days, but the question does not say “exactly”.
- **None.** In a leap year February has 29, but it still has a 28th day, and so does every other month.