How to Appear to Read Someone's Mind with Numbers
Ask your friend to pick a number., Have your friend double the number., Show him 10 fingers., Divide the answer by 2., Subtract the original number., Announce that the answer is 5., Know why this works.
Step-by-Step Guide
-
Step 1: Ask your friend to pick a number.
He should keep this number secret from you.
Tell him not to forget, since he'll have to remember it later.
We'll go through an example where your friend picks the number
6.
Even kids can do the math in this trick, as long as they can multiply and divide by
2.
A young kid might need to whisper the number to another person, so she can remind him later. -
Step 2: Have your friend double the number.
Say "Now double the number you chose, but don't tell me the answer." In our example, 6 x 2 =
12. , Ask him to add 10 to his last answer. 12 + 10 =
22. , Tell your friend you're trying to read his mind, but the number is too big right now.
Ask him to divide the answer by 2 to make it smaller. 22 ÷ 2 =
11. , Ask him to take the last answer and subtract the original number he picked.
The person in our example picked 6, so he would calculate 11
- 6 =
5. , No matter what number your friend chose, he will end up with 5 as his final answer.
Announce that you have read his mind, and the last number your friend wrote down is
5.
If there are other people in the room, have your friend show them the piece of paper to prove it. , Most of these steps are there just to make it hard for people to follow the problem.
After you double the chosen number, divide it by two, and subtract the number, you've cancelled out the original number completely.
Now it doesn't matter what your friend chose.
The answer only depends on the extra numbers and instructions you gave him, which happen to lead to 5 in this trick. -
Step 3: Show him 10 fingers.
-
Step 4: Divide the answer by 2.
-
Step 5: Subtract the original number.
-
Step 6: Announce that the answer is 5.
-
Step 7: Know why this works.
Detailed Guide
He should keep this number secret from you.
Tell him not to forget, since he'll have to remember it later.
We'll go through an example where your friend picks the number
6.
Even kids can do the math in this trick, as long as they can multiply and divide by
2.
A young kid might need to whisper the number to another person, so she can remind him later.
Say "Now double the number you chose, but don't tell me the answer." In our example, 6 x 2 =
12. , Ask him to add 10 to his last answer. 12 + 10 =
22. , Tell your friend you're trying to read his mind, but the number is too big right now.
Ask him to divide the answer by 2 to make it smaller. 22 ÷ 2 =
11. , Ask him to take the last answer and subtract the original number he picked.
The person in our example picked 6, so he would calculate 11
- 6 =
5. , No matter what number your friend chose, he will end up with 5 as his final answer.
Announce that you have read his mind, and the last number your friend wrote down is
5.
If there are other people in the room, have your friend show them the piece of paper to prove it. , Most of these steps are there just to make it hard for people to follow the problem.
After you double the chosen number, divide it by two, and subtract the number, you've cancelled out the original number completely.
Now it doesn't matter what your friend chose.
The answer only depends on the extra numbers and instructions you gave him, which happen to lead to 5 in this trick.
About the Author
John Young
Experienced content creator specializing in practical skills guides and tutorials.
Rate This Guide
How helpful was this guide? Click to rate: