To solve for the unknown value using a variation model, we start with the formula for Body Mass Index (BMI):
where
Step 1: Find the constant
We know the BMI for a 179-lb person who is 68 in tall is 27.21. Plugging these values into the equation:
Calculating
Now substitute this into the equation:
To isolate
Calculating
Now, we multiply:
Step 2: Use to find the BMI for the 128-lb person who is 60 in tall
Now we use the constant
Calculating
Now substitute this back into the equation:
Calculating
Now, substitute this into the equation for BMI:
Conclusion
The body mass index (BMI) for an individual who is 60 inches tall and weighs 128 pounds is approximately: