TACHS Math : Proportions

Study concepts, example questions & explanations for TACHS Math

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Example Questions

Example Question #1 : Proportions

Solve for the missing variable in the following proportion:

\(\displaystyle \frac{8}{3}=\frac{x}{9}\)

Possible Answers:

\(\displaystyle 24\)

\(\displaystyle 12\)

\(\displaystyle 15\)

\(\displaystyle 18\)

\(\displaystyle 36\)

Correct answer:

\(\displaystyle 24\)

Explanation:

Proportions are ratios that are equal to one another. We can solve for the missing variable by using cross multiplication to develop an equation.

\(\displaystyle \frac{8}{3}\times\frac{x}{9}\)

\(\displaystyle 8\times 9=x\times 3\)

Simplify.

\(\displaystyle 72=3x\)

Divide both sides of the equation by \(\displaystyle 3\).

\(\displaystyle \frac{72}{3}=\frac{3x}{3}\)

Solve.

\(\displaystyle x=24\)

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