Question

dave is comparing the circumferences of several trees in his yard. the oak tree is 0.539 meters in circumference, the ash tree has a circumference of 0.509 yards, the elm tree is 6281.70 millimeters around, and the poplar has a circumference of 0.000385 miles. there are 30.48 centimeters in a foot. which tree has the greatest circumference?
a. oak
b. ash
c. elm
d. poplar

Explanation:

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<reasoning>

Convert all measurements to meters

Using the Unit Conversion and Dimensional Analysis knowledge points
\[

$$\begin{aligned} &\text{Oak: } 0.539\text{ m}\\ &\text{Ash: } 0.509\text{ yd} \times \frac{36\text{ in}}{1\text{ yd}} \times \frac{2.54\text{ cm}}{1\text{ in}} \times \frac{1\text{ m}}{100\text{ cm}} = 0.509 \times 0.9144\text{ m} \approx 0.4654\text{ m}\\ &\text{Elm: } 6281.70\text{ mm} \times \frac{1\text{ m}}{1000\text{ mm}} = 6.2817\text{ m}\\ &\text{Poplar: } 0.000385\text{ mi} \times \frac{5280\text{ ft}}{1\text{ mi}} \times \frac{30.48\text{ cm}}{1\text{ ft}} \times \frac{1\text{ m}}{100\text{ cm}} = 0.000385 \times 1609.344\text{ m} \approx 0.6196\text{ m} \end{aligned}$$

\]

Compare the converted values

Using the Unit Conversion knowledge point
\[

$$\begin{aligned} &\text{Elm: } 6.2817\text{ m}\\ &\text{Poplar: } 0.6196\text{ m}\\ &\text{Oak: } 0.539\text{ m}\\ &\text{Ash: } 0.4654\text{ m}\\ &6.2817\text{ m} > 0.6196\text{ m} > 0.539\text{ m} > 0.4654\text{ m} \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>a. oak</mcq-option>
<mcq-option>b. ash</mcq-option>
<mcq-correct>c. elm</mcq-correct>
<mcq-option>d. poplar</mcq-option>
</answer>

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Answer:

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<reasoning>

Convert all measurements to meters

Using the Unit Conversion and Dimensional Analysis knowledge points
\[

$$\begin{aligned} &\text{Oak: } 0.539\text{ m}\\ &\text{Ash: } 0.509\text{ yd} \times \frac{36\text{ in}}{1\text{ yd}} \times \frac{2.54\text{ cm}}{1\text{ in}} \times \frac{1\text{ m}}{100\text{ cm}} = 0.509 \times 0.9144\text{ m} \approx 0.4654\text{ m}\\ &\text{Elm: } 6281.70\text{ mm} \times \frac{1\text{ m}}{1000\text{ mm}} = 6.2817\text{ m}\\ &\text{Poplar: } 0.000385\text{ mi} \times \frac{5280\text{ ft}}{1\text{ mi}} \times \frac{30.48\text{ cm}}{1\text{ ft}} \times \frac{1\text{ m}}{100\text{ cm}} = 0.000385 \times 1609.344\text{ m} \approx 0.6196\text{ m} \end{aligned}$$

\]

Compare the converted values

Using the Unit Conversion knowledge point
\[

$$\begin{aligned} &\text{Elm: } 6.2817\text{ m}\\ &\text{Poplar: } 0.6196\text{ m}\\ &\text{Oak: } 0.539\text{ m}\\ &\text{Ash: } 0.4654\text{ m}\\ &6.2817\text{ m} > 0.6196\text{ m} > 0.539\text{ m} > 0.4654\text{ m} \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>a. oak</mcq-option>
<mcq-option>b. ash</mcq-option>
<mcq-correct>c. elm</mcq-correct>
<mcq-option>d. poplar</mcq-option>
</answer>

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