Algebra practice question

Answer: 40

0.3x − 3 = 0.2x + 1 → 0.1x = 4 → x = 40.

Common wrong answers

If you answered 4

4 is 0.1x, before dividing by 0.1.

If you answered 110

110 comes from 0.3x − 10 = 0.2x + 1, forgetting to multiply the 10 by 0.3.

If you answered -20

−20 comes from 0.1x = −2, subtracting the constants in the wrong order.

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