Grade 5

Write this problem on the board and encourage students to use an organize strategy to solve.

In the U.S., we can write May 2, 2007 as 5/2/2007. In Europe and South America, the same date is written as 2/5/2007. How many other dates in the year are unclear if you don’t know where the writer is from?

- There are 12 months, so you only have to worry about the first 12 days of each month.
- Except, if the number of the month and the date are the same, then it’s written the same way.
- So, in each month there are eleven dates that can be misread.
- This gives 12 × 11, or 132 dates per year.

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