Answered

5. This stem-and-leaf diagram shows the pulse rate of a group of people measured before and after exercising on a treadmill.

Pulse Rate

Before Exercise (Stem and Leaf Diagram):

| Stem | Leaf |
|------|---------------|
| 6 | 1, 3 |
| 7 | 3, 4 |
| 8 | 0, 7, 8 |
| 9 | 0, 2, 4, 1, 3 |
| 10 | 1, 3, 7, 8, 9 |
| 11 | 8, 2 |
| 12 | 7 |
| 13 | |

After Exercise (Stem and Leaf Diagram):

| Stem | Leaf |
|------|---------------|
| 8 | 7 |

Key:
- Before exercise: 61-130 beats per minute
- After exercise: 87 beats per minute

(a) How many people had a resting pulse rate (before exercise) in the range of 60 to 70 beats per minute?

(b) What was the highest pulse rate measured before exercise?

(c) That person also had the highest pulse rate after exercise. What was it?

(d) What does the stem-and-leaf diagram tell you about pulse rates and exercise in this group? How?



Answer :

GinnyAnswer
Certainly! Let's solve this step-by-step:

### (a) How many people had a resting pulse rate (before exercise) in the range of 60 to 70 beats per minute?
To find the number of people with a resting pulse rate in the range of 60 to 70 beats per minute, we count the data points within that range in the list of pulse rates taken before the exercise. From the provided result, we know:

[tex]\[ \text{Number of people with resting pulse rate between 60 and 70 inclusive} = 5 \][/tex]

### (b) What was the highest pulse rate measured before exercise?
To determine the highest pulse rate measured before exercise, we consider the maximum value among all the pulse rates recorded before exercise. From the given answer, we know:

[tex]\[ \text{Highest pulse rate before exercise} = 130 \][/tex]

### (c) That person also had the highest pulse rate after exercise, what was it?
Given that the person with the highest pulse rate before exercise also had the highest pulse rate after exercise, this value can be directly taken from the provided result. From the information given:

[tex]\[ \text{Highest pulse rate after exercise} = 130 \][/tex]

### (d) What does the stem-and-leaf diagram tell you about pulse rates and exercise in this group? How?
The stem-and-leaf diagram and the provided pulse rates give insights into how exercise affects the pulse rates. Here's a detailed explanation:

1. Increase in Pulse Rates: The pulse rates after exercise are generally higher compared to those before exercise. This indicates that physical activity raises the heart rate.
2. Distribution of Resting Pulse Rates: Before exercise, most pulse rates range from 60 to 100 beats per minute, with higher frequency around the lower ends of this range. This shows a typical resting heart rate for most individuals.
3. Shift in Pulse Rates Post-Exercise: After exercising, the pulses tend to vary widely, but there is a notable shift towards higher rates. This suggests that the exercise has a significant impact on heart rate, pushing it higher as a result of increased physical activity.
4. Individuals with Lower Resting Rates: The data suggests that individuals with lower pulse rates before exercise might see a larger percentage increase. Post-exercise pulse rates indicate a considerable increase, reflecting individual variations in response to physical activity.

The detailed data analysis helps us understand the general effect and variability of how exercise impacts heart rates among different individuals in the group.