During exercise, the recommended maximum heart rate in beats per minute is modeled by the formula M = 176 – 0.8A, where M is the maximum heart rate and A is the person’s age. Approximately, at what age would you have a recommended heart rate in beats per minute of 140?
We can start by setting the formula equal to 140 and solving for A:
176 - 0.8A = 140
Subtracting 176 from both sides, we get:
-0.8A = -36
Dividing both sides by -0.8, we get:
A = 45
Therefore, at approximately 45 years of age, a person would have a recommended heart rate of 140 beats per minute during exercise.
To find the age at which the recommended heart rate is 140 beats per minute, we need to substitute M = 140 into the formula M = 176 - 0.8A and solve for A.
Here's how you can solve it step by step:
Step 1: Substitute M = 140 into the formula:
140 = 176 - 0.8A
Step 2: Rearrange the equation by isolating A:
0.8A = 176 - 140
Step 3: Simplify the right side of the equation:
0.8A = 36
Step 4: Divide both sides of the equation by 0.8 to solve for A:
A = 36 / 0.8
Step 5: Calculate the division:
A = 45
Therefore, the approximate age at which you would have a recommended heart rate of 140 beats per minute is 45 years old.
To find the age at which the recommended heart rate is 140 beats per minute, we can substitute M = 140 into the given formula and solve for A.
M = 176 - 0.8A
Substituting M = 140:
140 = 176 - 0.8A
Rearranging the equation to solve for A:
0.8A = 176 - 140
0.8A = 36
Dividing both sides by 0.8:
A = 36 / 0.8
A = 45
Therefore, at approximately age 45, a person would have a recommended heart rate of 140 beats per minute during exercise.