To solve this problem, we need to understand the correct steps involved in converting 720 seconds into hours, and then identify which step the student skipped in their incorrect conversion.
### Correct Conversion Steps:
1. Convert Seconds to Minutes:
To convert seconds to minutes, we use the conversion ratio [tex]\(\frac{1 \text{ minute}}{60 \text{ seconds}}\)[/tex].
[tex]\[
720 \text{ seconds} \times \left(\frac{1 \text{ minute}}{60 \text{ seconds}}\right) = 12 \text{ minutes}
\][/tex]
Now, we have 12 minutes.
2. Convert Minutes to Hours:
To convert minutes to hours, we use the conversion ratio [tex]\(\frac{1 \text{ hour}}{60 \text{ minutes}}\)[/tex].
[tex]\[
12 \text{ minutes} \times \left(\frac{1 \text{ hour}}{60 \text{ minutes}}\right) = 0.2 \text{ hours}
\][/tex]
### Incorrect Conversion:
The student directly used:
[tex]\[
720 \text{ seconds} \times \left(\frac{1 \text{ hour}}{60 \text{ minutes}}\right) = 12 \text{ hours}
\][/tex]
Here, the student has incorrectly converted seconds to hours by using the ratio [tex]\(\frac{1 \text{ hour}}{60 \text{ minutes}}\)[/tex] which is not suitable for converting seconds directly to hours.
### Identifying the Skipped Step:
The student skipped converting seconds into minutes first. The required intermediate conversion should be:
Conversion Ratio: [tex]\(\frac{1 \text{ minute}}{60 \text{ seconds}}\)[/tex]
Thus, the skipped conversion ratio is:
[tex]\[
\boxed{\frac{1 \text{ minute}}{60 \text{ seconds}}}
\][/tex]
So the correct answer is:
A. [tex]\(\frac{1 \text { minute }}{60 \text { seconds }}\)[/tex]
