How to Trick Friends with the 5000 Number Adding Trick

Last Updated: August 10, 2021

Trick your friends with this basic math problem, with no magician skills required. Although it's nothing but addition, the pattern tricks most people into making a mistake.

Steps

1
Ask a friend to listen to your magic trick. Tell your friend that you won't need any special props. You'll just ask them to add together numbers in their head.
2
Tell your friend to take 1000 and add 40. Tell them to hold the answer in their head. They do not need to say it out loud.

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3
Instruct them to add another 1000. At this point, your friend should be thinking of 2040.
4
Have your friend add another 30. Give your commands slowly. Allow your friend plenty of time to do the addition.
5
Add another 1000. We're up to 3070 now, assuming your friend hasn't made a mistake.
6
Add 20. Tell your friend to add 20, still keeping the number to themself.
7
Add one last 1000. Say that you'll add 1000 one last time, and that you're nearly done. Your friend should now be thinking of 4090.
8
Ask what you get when you add 10 to the number they're thinking of. Say "Now add 10 and tell me the answer." If your friend hesitates, encourage them by saying, "you know the answer, what is it?"
9
Tell your friend the correct answer. Most people will answer "5000" but this is not the right answer! 4090 + 10 actually equals 4100. It's an easy mistake to make when speaking aloud, since the trick makes you think you're counting up to a big even number. You might need to write it on a piece of paper for your friend to believe it.