Question

rob is going over his currency exchange receipts from his trip to japan and south korea. when he was in japan, he exchanged us dollars for japanese yen at a rate of 1:87.441, and when he was in south korea, he exchanged japanese yen for south korean won at a rate of 1:12.395. to three decimal places, what was the exchange rate of us dollars to south korean won?
a. 1:0.092
b. 1:7.055
c. 1:99.836
d. 1:1,083.831

Explanation:

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<reasoning>

Identify the given exchange rates

Using the Currency Exchange Rates knowledge point
\[

$$\begin{aligned} &1\text{ USD} = 87.441\text{ JPY}\\ &1\text{ JPY} = 12.395\text{ KRW} \end{aligned}$$

\]

Calculate the direct exchange rate from USD to KRW

Using the Currency Exchange Rates knowledge point
\[

$$\begin{aligned} 1\text{ USD} &= 87.441 \times 12.395\text{ KRW}\\ 1\text{ USD} &= 1083.831195\text{ KRW} \end{aligned}$$

\]

Round to three decimal places and match the option

Using the Currency Exchange Rates knowledge point
\[

$$\begin{aligned} &1\text{ USD} \approx 1083.831\text{ KRW}\\ &\text{Exchange Rate Ratio} = 1:1,083.831 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>a. 1:0.092</mcq-option>
<mcq-option>b. 1:7.055</mcq-option>
<mcq-option>c. 1:99.836</mcq-option>
<mcq-correct>d. 1:1,083.831</mcq-correct>
</answer>

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Answer:

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<reasoning>

Identify the given exchange rates

Using the Currency Exchange Rates knowledge point
\[

$$\begin{aligned} &1\text{ USD} = 87.441\text{ JPY}\\ &1\text{ JPY} = 12.395\text{ KRW} \end{aligned}$$

\]

Calculate the direct exchange rate from USD to KRW

Using the Currency Exchange Rates knowledge point
\[

$$\begin{aligned} 1\text{ USD} &= 87.441 \times 12.395\text{ KRW}\\ 1\text{ USD} &= 1083.831195\text{ KRW} \end{aligned}$$

\]

Round to three decimal places and match the option

Using the Currency Exchange Rates knowledge point
\[

$$\begin{aligned} &1\text{ USD} \approx 1083.831\text{ KRW}\\ &\text{Exchange Rate Ratio} = 1:1,083.831 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>a. 1:0.092</mcq-option>
<mcq-option>b. 1:7.055</mcq-option>
<mcq-option>c. 1:99.836</mcq-option>
<mcq-correct>d. 1:1,083.831</mcq-correct>
</answer>

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