Tell students that you are going to test their division skills by doing the following experiment:
1. Pick any three-digit number that you wish.
2. Write it down then write it down again to make a six-digit number.
For example, if you chose 428, then write down 428428.
3. Now divide this six-digit number by 7. You shouldn't get a remainder.
4. Divide the quotient by 11, again you shouldn't get a remainder.
5. Divide that quotient by 13, and again you shouldn't get a remainder.
6. What is your answer?
How does it work?
|You should get your original answer back.|
|When you formed the six digit number, you actually multiplied by 1,001.|
|The factors of 1,001 are 7, 11, and 13.|