Question

patrick laid a pencil and a candle end-to-end. the pencil is 15.80 centimeters long, the candle is 0.303 yards long. there are 30.48 centimeters in a foot. how many inches long are the two items placed end-to-end?
a. 0.48 in
b. 16.10 in
c. 17.13 in
d. 43.51 in

Explanation:

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<reasoning>

Convert pencil length to inches

Using the Unit Conversion and Dimensional Analysis knowledge points
\[

$$\begin{aligned} L_{\text{pencil}} &= 15.80\text{ cm} \times \frac{1\text{ ft}}{30.48\text{ cm}} \times \frac{12\text{ in}}{1\text{ ft}} \\ L_{\text{pencil}} &= 15.80 \times \frac{12}{30.48}\text{ in} \\ L_{\text{pencil}} &\approx 6.22047\text{ in} \end{aligned}$$

\]

Convert candle length to inches

Using the Unit Conversion and Dimensional Analysis knowledge points
\[

$$\begin{aligned} L_{\text{candle}} &= 0.303\text{ yards} \times \frac{36\text{ in}}{1\text{ yard}} \\ L_{\text{candle}} &= 10.908\text{ in} \end{aligned}$$

\]

Calculate total length

Using the Unit Conversion knowledge point
\[

$$\begin{aligned} L_{\text{total}} &= L_{\text{pencil}} + L_{\text{candle}} \\ L_{\text{total}} &\approx 6.22047\text{ in} + 10.908\text{ in} \\ L_{\text{total}} &\approx 17.12847\text{ in} \approx 17.13\text{ in} \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>(a) 0.48 in</mcq-option>
<mcq-option>(b) 16.10 in</mcq-option>
<mcq-correct>(c) 17.13 in</mcq-correct>
<mcq-option>(d) 43.51 in</mcq-option>
</answer>

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Answer:

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<reasoning>

Convert pencil length to inches

Using the Unit Conversion and Dimensional Analysis knowledge points
\[

$$\begin{aligned} L_{\text{pencil}} &= 15.80\text{ cm} \times \frac{1\text{ ft}}{30.48\text{ cm}} \times \frac{12\text{ in}}{1\text{ ft}} \\ L_{\text{pencil}} &= 15.80 \times \frac{12}{30.48}\text{ in} \\ L_{\text{pencil}} &\approx 6.22047\text{ in} \end{aligned}$$

\]

Convert candle length to inches

Using the Unit Conversion and Dimensional Analysis knowledge points
\[

$$\begin{aligned} L_{\text{candle}} &= 0.303\text{ yards} \times \frac{36\text{ in}}{1\text{ yard}} \\ L_{\text{candle}} &= 10.908\text{ in} \end{aligned}$$

\]

Calculate total length

Using the Unit Conversion knowledge point
\[

$$\begin{aligned} L_{\text{total}} &= L_{\text{pencil}} + L_{\text{candle}} \\ L_{\text{total}} &\approx 6.22047\text{ in} + 10.908\text{ in} \\ L_{\text{total}} &\approx 17.12847\text{ in} \approx 17.13\text{ in} \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>(a) 0.48 in</mcq-option>
<mcq-option>(b) 16.10 in</mcq-option>
<mcq-correct>(c) 17.13 in</mcq-correct>
<mcq-option>(d) 43.51 in</mcq-option>
</answer>

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