Think of a number

Everyone’s final answer will be 1

1. Pick a whole number between 1 and 10.
2. Add 2.
3. Multiply by 2.
4. Subtract 2.
5. Divide by 2.
6. Subtract your original number.
7. Answer will be 1.

Think of a 3 digit number

1. Pick a 3-digit number with all three digits different.
2. Reverse the digits and subtract to get another 3-digit number.
3. Reverse the digits of the difference and add it to the difference.
4. Your sum will be 1089.

Example: 329 → 923 − 329 = 594; 594 + 495 = 1089.

Dicey

Ask them to roll two dice secretly (e.g., 4 and 6).

1. Multiply first die by 2.
2. Add 5.
3. Multiply by 5.
4. Add the second die.
5. Subtract 25 from the final number. The two digits reveal the dice: first digit = first die, second digit = second die.

Example: 4 → 4×2=8; +5=13; ×5=65; +6=71; 71−25=46 ⇒ 4 & 6.

Think of a number

Everyone’s final answer will be 5

1. Pick a whole number.
2. Double the number.
3. Add 10.
4. Divide by 2.
5. Subtract the original number.
6. Your answer will be 5.

Card Trick

1. Peek the 10th card in the deck and memorize it.
2. Ask them to choose a number between 10 and 20. Deal that many cards to make a small pile.
3. Have them add the digits of their number (e.g., 12 → 1+2=3).
4. Count that many cards from the small pile and give the next one to them.
5. It will be the 10th card you memorized.

Cloning the number

Think of any 3-digit number.

1. Multiply by 7.
2. Multiply by 11.
3. Multiply by 13.
4. The result is a 6-digit number that repeats the original number twice (e.g., 123 → 123123).

Finding age

1. Write your lucky number (1–9).
2. ×2, then +5, then ×50.
3. Add 1775 if your birthday has occurred this year, else add 1774.
4. Subtract your birth year.
5. The result is 3 digits: first is your lucky number, last two are your age.

Guessing the number in your mind

1. Think of any number.
2. ×2, +2, ×5.
3. Remove the rightmost digit; the remaining number − 1 equals your original number.

Think of a number(Credit: Hasan Bhoira, DPS Monarch, Qatar)

Everyone’s final answer will be 10

1. Think of any number.
2. Multiply by 2.
3. Add 20.
4. Divide by 2.
5. Subtract your original number.
6. Your answer will be 10.

Birthday Trick

1. Multiply your birth month (Jan=1…Dec=12) by 4.
2. Add 12.
3. Divide by 2.
4. Multiply by 100.
5. Divide by 2.
6. Add your birth date.
7. Subtract 300.
8. Result shows month (first 1–2 digits) and day (last 2 digits).

Slot for our students

During the next Contest of Math Titans, win free Math Olympiad registrations. Stay tuned—this slot will showcase top student submissions and announcements.

Slot for our students

Reserve your spot to feature your best magic-math trick. Winners earn free Math Olympiad registrations and social highlights on MathsJadugar.