Answer :

First of all we need to realize that half of a yard is as much as 18 inches. If a diameter of the circle is 18 inches, then its radius is 18 ÷ 2 = 9 inches.

The measures of the diameter and the radius, are illustrations of unit conversions

The radius of the circle is 9 inches

The diameter (d) is given as:

[tex]\mathbf{d = \frac{1}{2}\ yard}[/tex]

Multiply by 36 to convert the unit from yard to inches

[tex]\mathbf{d = 36 \times \frac{1}{2}\ inches}[/tex]

[tex]\mathbf{d = 18\ inches}[/tex]

Divide both sides by 2, to get the radius

[tex]\mathbf{r = \frac{d}{2} = \frac{18}{2}\ inches}[/tex]

[tex]\mathbf{r = 9\ inches}[/tex]

Hence, the radius of the circle is 9 inches

Read more about unit conversions at:

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