PHAR 4330

Calculating BMI Using Formula

Body Mass Index (BMI) can be determined using a formula with the weight and height of the individual in kilogram and meter respectively.

$BMI = {Weight\ (kg) \over [Height\ (m)] ^2}$

BMI can also be determined using a formula with weight and height of the individual in pounds and inches respectively.

$BMI = {Weight\ (lb) \over [Height\ (inch)] ^2} \times {704.5}$

Solved Problem: Calculate the BMI of a person weighing 50 kg and measuring 5 feet.

Approach: Convert feet into meters, and use the formula for BMI with weight in kg and height in meters.

$5\ feet = {5\ feet} \times {12\ inches \over 1\ feet} = 60\ inches$

$60\ inches \times {2.54\ cm \over 1\ inch} = 152.4\ cm = 1.524\ meters$

$BMI = {50\ kg \over [1.524\ m] ^2} = {21.5}$

Answer: 21.5

Solved Problem: Calculate the BMI of a person weighing 110 lb and measuring 5 feet. .

Approach: Convert feet into inches, and use the formula for BMI with weight in lb and height in inches.

$5\ feet = {5\ feet} \times {12\ inches \over 1\ feet} = 60\ inches$

$BMI = {110\ lb \over [60\ inches] ^2} \times {704.5}=21.5$

Answer: 21.5