Conduct an investigation to determine the effect of exercise on the pulse rate of a person.

The goal of step 4 is to calculate the average pulse rate while at rest using multiple readings to ensure accuracy and reliability of the data.

According to the procedure, you will have three pulse rate readings taken while your partner is at rest:

• The first reading from step 3.
• Two additional readings as instructed in step 4.

To calculate the average pulse rate, sum the three readings and then divide by the number of readings (which is 3).

Let $P_1$, $P_2$, and $P_3$ be the three pulse rate readings (beats per minute) taken at rest.
The formula for the average pulse rate ($\text{Average } P$) is:

Suppose your three pulse rate readings at rest are 70 beats/min, 72 beats/min, and 68 beats/min.