First step: identify how many heart beats in a year.
To determine the heart beats in a year multiply the heart beats in a minute with [tex](60\times 24\times 365)[/tex] years.
Thus, heart beats in a year comes out to be = [tex]71 \times (60\times 24\times 365) years[/tex]
= [tex]37317600[/tex] heart beats in a year
Heart beats [tex]3.1\times 10^{9}[/tex] in a life time.
Thus, number of years he lives is calculated by the division of heart beats in a year and heart beats in a life time.
Number of years he lives = [tex]\frac{3.1\times 10^{9}}{37317600}[/tex]
= [tex]8.3\times 10^{-8}\times 10^{9}[/tex]
= [tex]8.3\times 10[/tex]
= [tex]83.0 [/tex] years
Thus, number of years he lives is [tex]83.0 [/tex] years
