The Rule / āύāĻŋāϝāĻŧāĻŽ: Reverse a 2-digit number and subtract. (āĻāĻāĻž ⧍ āĻ
āĻāĻā§° āϏāĻāĻā§āϝāĻž āĻāϞā§āĻāĻžāĻ āĻŦāĻŋāϝāĻŧā§āĻ āĻā§°āĻāĨ¤)
Magic Result / āĻāĻžāĻĻā§āĻā§°ā§ āĻĢāϞāĻžāĻĢāϞ
The answer is always a multiple of 9. (āĻāϤā§āϤ⧰ āϏāĻĻāĻžāϝāĻŧ ⧝ ā§° āĻā§āĻŖāĻŋāϤāĻ āĻšāϝāĻŧāĨ¤)
How It Works / āĻā§āύā§āĻā§ āĻāĻžāĻŽ āĻā§°ā§
- Take any 2-digit number. (āϝāĻŋāĻā§āύ⧠⧍ āĻ
āĻāĻā§° āϏāĻāĻā§āϝāĻž āϞāĻāĻāĨ¤)
- Reverse the digits. (āĻ
āĻāĻāĻŦā§ā§° āĻāϞā§āĻāĻžāĻ āĻĻāĻŋāϝāĻŧāĻāĨ¤)
- Subtract the smaller from the larger. (āĻĄāĻžāĻā§° āϏāĻāĻā§āϝāĻžā§° āĻĒā§°āĻž āϏ⧰⧠āϏāĻāĻā§āϝāĻžāĻā§ āĻŦāĻŋāϝāĻŧā§āĻ āĻā§°āĻāĨ¤)
Examples / āĻāĻĻāĻžāĻšā§°āĻŖ
- 52 → 25, 52 − 25 = 27, 27 is a multiple of 9. (27 āĻšā§āĻ⧠⧝ ā§° āĻā§āĻŖāĻŋāϤāĻāĨ¤)
- 81 → 18, 81 − 18 = 63, 63 is a multiple of 9. (63 āĻšā§āĻ⧠⧝ ā§° āĻā§āĻŖāĻŋāϤāĻāĨ¤)
- 73 → 37, 73 − 37 = 36, 36 is a multiple of 9. (36 āĻšā§āĻ⧠⧝ ā§° āĻā§āĻŖāĻŋāϤāĻāĨ¤)
- 94 → 49, 94 − 49 = 45, 45 is a multiple of 9. (45 āĻšā§āĻ⧠⧝ ā§° āĻā§āĻŖāĻŋāϤāĻāĨ¤)
Key Idea / āĻŽā§āϞ āϧāĻžā§°āĻŖāĻž: Reversing digits creates a hidden 9-pattern. (āĻ
āĻāĻ āĻāϞā§āĻāĻžāϞ⧠āĻāĻāĻž āϞā§āĻāĻžāĻ āĻĨāĻāĻž ⧝-ā§° pattern āϏā§āώā§āĻāĻŋ āĻšāϝāĻŧāĨ¤)
52 − 25 = 27, 81 − 18 = 63, 73 − 37 = 36, 94 − 49 = 45
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MCQ
1. What happens in the number reversal trick ? / Number reversal trick āϤ āĻāĻŋ āĻā§°āĻž āĻšāϝāĻŧ ?
A. Numbers are added / āϏāĻāĻā§āϝāĻž āϝā§āĻ āĻā§°āĻž āĻšāϝāĻŧ
B. Numbers are multiplied / āϏāĻāĻā§āϝāĻž āĻā§āĻŖ āĻā§°āĻž āĻšāϝāĻŧ
C. Digits are reversed and subtracted / āĻ
āĻāĻ āĻāϞā§āĻāĻžāĻ āĻŦāĻŋāϝāĻŧā§āĻ āĻā§°āĻž āĻšāϝāĻŧ
D. Numbers are divided / āϏāĻāĻā§āϝāĻž āĻāĻžāĻ āĻā§°āĻž āĻšāϝāĻŧ
Ans / āĻāϤā§āϤ⧰: C. Digits are reversed and subtracted / āĻ
āĻāĻ āĻāϞā§āĻāĻžāĻ āĻŦāĻŋāϝāĻŧā§āĻ āĻā§°āĻž āĻšāϝāĻŧ
2. What is the result always a multiple of ? / āĻĢāϞāĻžāĻĢāϞ āϏāĻĻāĻžāϝāĻŧ āĻāĻŋāĻšā§° āĻā§āĻŖāĻŋāϤāĻ āĻšāϝāĻŧ ?
A. 5 B. 7 C. 8 D. 9
Ans / āĻāϤā§āϤ⧰: D. 9
3. Reverse of 52 is — / 52 ā§° āĻāϞā§āĻāĻž āϏāĻāĻā§āϝāĻž āĻšā§āĻā§ —
A. 15 B. 25 C. 72 D. 35
Ans / āĻāϤā§āϤ⧰: B. 25
4. 81 − 18 = ?
A. 54 B. 63 C. 72 D. 45
Ans / āĻāϤā§āϤ⧰: B. 63
5. Reverse of 73 is - / 73 ā§° āĻāϞā§āĻāĻž āϏāĻāĻā§āϝāĻž āĻšā§āĻā§ -
A. 37 B. 27 C. 47 D. 17