To find the lower part of the target heart rate zone for a 15-year-old, we need to evaluate each of the given equations and see what the results are for these calculations. Let's proceed step by step:
1. Evaluate \(200 \times 0.65\):
[tex]\[
200 \times 0.65 = 130.0
\][/tex]
2. Evaluate \(190 \times 0.65\):
[tex]\[
190 \times 0.65 = 123.5
\][/tex]
3. Evaluate \(205 \times 0.65\):
[tex]\[
205 \times 0.65 = 133.25
\][/tex]
4. Evaluate \(200 \times 0.75\):
[tex]\[
200 \times 0.75 = 150.0
\][/tex]
Now, we have the results of all the equations:
- \(200 \times 0.65 = 130.0\)
- \(190 \times 0.65 = 123.5\)
- \(205 \times 0.65 = 133.25\)
- \(200 \times 0.75 = 150.0\)
In the context of a 15-year-old's lower part of their target heart rate zone, we need to identify which value fits. The target heart rate zone is typically calculated as a percentage of the maximum heart rate, often considered around 65% for the lower part of the zone.
Based on these calculations, [tex]\( 190 \times 0.65 = 123.5 \)[/tex] is the correct value that represents the lower part of the target heart rate zone more accurately for a 15-year-old.
