My birthday is coming up this week and I was reminded of a couple of tricks you can use to impress your friends. Just a few math calculations and you will amaze everyone by producing their birthday in numbers!

Warning! You may want to use a calculator!

Trick 1: Produce your birth month and day

Explain that you will have them complete a set of math problems and based on the result they provide, you will know their birthday!

Now, you will need to complete the next three steps. Don’t tell your friend what you are doing!

10) Ask your friend for their answer.

11) Mentally add 11.

12) Mentally divide by 100.

Voila! The result you get tells you their birth month and year. The birth month is the whole number and the birth day is the number following the decimal point. For example, I follwed the steps and my answer was 1.15! The whole number 1 is my birth month, January, and the 15 represents my birth day!

Not amazing enough for you? The following will not only tell you your birth month and day, it will also tell you your birth year!

Trick 2: Produce your birth month, day, and year

Explain that you will have them complete a set of math problems and based on the result they provide, you will know their birthday!

Now, you will need to complete steps 12 and 13. Don’t tell your friend what you are doing!

12) Ask your friend for their answer.

13) Subtract 32940.

Voila! The result you get tells you their birth month, birth day, and birth year. After following the 13 steps, my answer was 11,5xx! How amazing is that! And yes, I replaced the last two digits of my birth year because I am a lady and I’ll never tell ðŸ˜‰

The Math Ninja in me wonders, how are these tricks possible?!? We must be able to explain these with math, but before we do, I want to give you a chance to be amazed and amaze others. Enjoy!

Thanks to Dr. Mike and Easy Calculation for sharing these tricks!

### Angela Culley

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Thanks for stopping by Ana! I love any and all tricks that will grab kids attention.

I love trying types of tricks like this — even for non-math ninjas like myself :).

Excited to connect this week from your SITS tribe!

Thanks for the birthday wish! 37 is bound to be a great year!

I’m glad you found it fun! You would have shocked me if you had said you were a math person! I hear how much people are not math people all of the time. Maybe a little of my math nerdiness will rub off on you during our SITS Tribe week!

I just told my husband how I am not a math person at all, but this was fun to try!

Stopping by from SITS Tribe!

That is fun – and happy belated birthday! Visiting you from the SITS tribe!

Agree, getting BOOBS as a calculator answer is definitely a favorite among the middle school crowd! I can remember that one from my own middle school days ðŸ™‚

Amazing!!

I always liked these sorts of tricks. Not as fun as getting BOOBS as a calculator answer, but nothing will ever be that fun.