Advanced Math practice question

Answer: 4

Let the number be x: 2x/(x − 2) = 4, so 2x = 4x − 8, 2x = 8, x = 4. Check: 8/2 = 4 ✓.

Common wrong answers

If you answered 2

2 makes 'two less than the number' zero, so the ratio is undefined.

If you answered 8

8 is the value of 2x, not of x.

If you answered -4

−4 comes from 2x = 4x + 8, a sign slip when distributing.

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