Multiple choice general knowledge math & puzzles

Think of a number greater than 0. Multiply by 2; add 5; multiply by 3; subtract the number you've thought of; divide by 5; subs tract the number again. The result is:

  1. 4

  2. 3

  3. 2

  4. 1
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let the number be x. Following steps: multiply by 2 gives 2x; add 5 gives 2x + 5; multiply by 3 gives 6x + 15; subtract x gives 5x + 15; divide by 5 gives x + 3; subtract x again gives 3. The operations are designed to cancel out the original number, leaving 3. This is an algebraic identity.

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