Question

Define the term `Body Mass Index'. Explain the method of its calculation.

Hint:

Remember the BMI formula: \[ \boxed{\text{BMI}=\frac{\text{Weight (kg)}}{\text{Height}^2\text{ (m}^2\text{)}}} \] Units:

• Weight -- Kilograms (kg)

• Height -- Metres (m)
Always square the height before dividing.

Answer 1

Step 1: Understand why BMI is useful.
Doctors need a simple way to check if someone's weight matches their height properly, and Body Mass Index gives them exactly that, a quick number that flags whether a person is underweight, normal, overweight, or obese.
Step 2: Write down how it is worked out.
\[ BMI = \dfrac{\text{Weight in kg}}{(\text{Height in metres})^2} \] You simply take a person's weight in kilograms and divide it by their height in metres squared.
Step 3: Run through a quick example.
For someone weighing 64 kg with a height of 1.60 m, the calculation is $64 \div (1.60)^2 = 64 \div 2.56 = 25$, giving a BMI of 25.
Step 4: State what the number tells us.
A BMI in the healthy range suggests proper nutrition, while a very low or very high value points to undernutrition or overweight respectively. Hence, BMI is calculated as weight in kilograms divided by height in metres squared, and it serves as a simple health screening tool.