Advanced Math practice question

Answer: 4

5 · 3ˣ = 405 gives 3ˣ = 81 = 3⁴, so x = 4.

Common wrong answers

If you answered 3

3 gives 5 · 27 = 135.

If you answered 5

5 gives 5 · 243 = 1215.

If you answered 81

81 is 3ˣ, not x.

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