AlgebraMediumUnknown from an average of expressions
Algebra practice question
The average (arithmetic mean) of x, 2x, and 3x + 6 is 14. What is the value of x?
Answer: 6
(x + 2x + 3x + 6)/3 = 14 → 6x + 6 = 42 → 6x = 36 → x = 6.
Common wrong answers
- If you answered 2
- 2 comes from 6x + 6 = 14, forgetting to multiply by 3.
- If you answered 7
- 7 comes from 6x = 42, forgetting the +6.
- If you answered 36
- 36 is 6x, before dividing.
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