Answer :
To solve the problem of finding how many jumping jacks Sara can do in [tex]\(\frac{7}{10}\)[/tex] of a minute, we can follow these steps:
1. Convert [tex]\(\frac{7}{10}\)[/tex] of a minute into seconds:
- Since there are 60 seconds in a minute, we first calculate how many seconds there are in [tex]\(\frac{7}{10}\)[/tex] of a minute.
- Multiply [tex]\(\frac{7}{10}\)[/tex] by 60:
[tex]\[
\frac{7}{10} \times 60 = 42 \text{ seconds}
\][/tex]
- This tells us that [tex]\(\frac{7}{10}\)[/tex] of a minute is the same as 42 seconds.
2. Determine how many jumping jacks can be done in 42 seconds:
- We know Sara can perform one jumping jack in [tex]\(\frac{3}{4}\)[/tex] of a second.
- To find out how many jumping jacks she can do in 42 seconds, we divide the total time available by the time it takes to do one jumping jack:
[tex]\[
42 \div \frac{3}{4} = \frac{42}{1} \times \frac{4}{3} = 42 \times \frac{4}{3} = 56
\][/tex]
- Therefore, Sara can do 56 jumping jacks in 42 seconds.
So, the correct formula to circle from the given options is:
[tex]\[
42 \div \frac{3}{4}
\][/tex]
This calculation shows us that in [tex]\(\frac{7}{10}\)[/tex] of a minute, Sara can perform exactly 56 jumping jacks.
1. Convert [tex]\(\frac{7}{10}\)[/tex] of a minute into seconds:
- Since there are 60 seconds in a minute, we first calculate how many seconds there are in [tex]\(\frac{7}{10}\)[/tex] of a minute.
- Multiply [tex]\(\frac{7}{10}\)[/tex] by 60:
[tex]\[
\frac{7}{10} \times 60 = 42 \text{ seconds}
\][/tex]
- This tells us that [tex]\(\frac{7}{10}\)[/tex] of a minute is the same as 42 seconds.
2. Determine how many jumping jacks can be done in 42 seconds:
- We know Sara can perform one jumping jack in [tex]\(\frac{3}{4}\)[/tex] of a second.
- To find out how many jumping jacks she can do in 42 seconds, we divide the total time available by the time it takes to do one jumping jack:
[tex]\[
42 \div \frac{3}{4} = \frac{42}{1} \times \frac{4}{3} = 42 \times \frac{4}{3} = 56
\][/tex]
- Therefore, Sara can do 56 jumping jacks in 42 seconds.
So, the correct formula to circle from the given options is:
[tex]\[
42 \div \frac{3}{4}
\][/tex]
This calculation shows us that in [tex]\(\frac{7}{10}\)[/tex] of a minute, Sara can perform exactly 56 jumping jacks.
