Question

The human body is approximately 60% of water, and one-half of the mass of the dry portion is protein. calculate the mass of protein in a 140. lb person.

Answer 1

Percentage of dry portion in human body $=100-60=40\%$

percentage of protein in human body=$\frac{40}2=20\%$

Mass of human body=$140lb$

Mass of protein in human body$=\frac{20}{100}\times140=28lb$

now,

$1lb=0.45359237 kg$

$28lb=28\times0.45359237 =12.7kg$

So, mass of protein in 140$lb$ person $=28lb=12.7kg$