The body-mass index (BMI) is a way of assessing people's weight
while taking into account their height. You can think of it as
how much a person weighs per inch of height. The BMI is a single
number because it is a ratio — in this case, the ratio between
weight and the square of one's height.
The basic equation uses metric units. It is weight in kilograms
divided by the square of height in meters and looks like this:
Your weight in kilograms (your height in
meters)2 = your body-mass index
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