Dr. David Smith lived 1/13 of his life as a child. He spent 4/39 of his life preparing for an outstanding
medical career. For 1/ 2 of his life, he was a successful surgeon in a famous children's hospital. Since his
retirement, he has lived 13 years on a comfortable pension. How old is he? (unrealistic answer))

Respuesta :

Answer:

40 14/25 years

Step-by-step explanation:

Well, this certainly is fun.

First, to find the fraction of the doctor's life which 13 years represents, subtract the fractions from 1 (and in this case l stands for lifetime):

[tex]13 = (1 - (\frac{1}{13} + \frac{4}{39} + \frac{1}{2}))(l)[/tex]

[tex]13 = (\frac{25}{78})(l)[/tex]

So, multiply this equation by the reciprocal of 25/78 to isolate one of l:

[tex]13(\frac{78}{25}) = l[/tex]

[tex]l = 40\frac{14}{25}[/tex] years