Advanced MathMediumPositive solution of a proportion with x on both sides
Advanced Math practice question
For what positive value of x is x/4 equal to 9/x?
Answer: 6
Cross-multiplying gives x² = 36, so x = 6.
Common wrong answers
- If you answered 36
- 36 is x², not x.
- If you answered 2.25
- 2.25 divides 9 by 4.
- If you answered -6
- −6 is ruled out because x is positive.
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