Question

❤ World War ❤

In 1940, a correspondent proposed the following question:

A man's age at death was one twenty-ninth of the year of his birth. How old was he in 1900?

Answer 1

Answer: He was 44 years old.

From the question you know the man died between 1900 and 1940.

We also know his age at death (x) is one twenty-ninth of the year of his birth (28x+1x).

If you add his age at death to the year he was born you get the year he died (30x). Only one year between 1900 and 1940 is divisible by 30, 1920 (the year he died).

The year he was born can now be found: 1920 * (29/30) = 1856. So in 1900 he was (1900 - 1856) = 44 years old.

Answer 2

Given,

A man's age at death = one twenty-ninth of the year of his birth

This was proposed in the year 1940, by his correspondent.

To find,

Age of the man in the year 1900.

Solution,

We can simply solve this mathematical problem using the following process:

Let us assume that the man died in the year x and his age at the time of death be y years.

According to the question;

The man must have died after 1900 but before 1940.

=> 1900 < x < 1940 {Equation-1}

Now, according to the question;

A man's age at death = one twenty-ninth of the year of his birth

=> y = 1/29(x-y)

=> x-y = 29y

=> x = 30y {Equation-2}

Now, substituting the value of x in equation-1, we get;

1900 < x < 1940

=> 1900 < 30y < 1940

=> 63.3 < y < 64.6

=> y = 64 years {Equation-3}

(Since, the actual age, in years, can only be a whole number)

Now,

The year of birth of the man

= (Year of death) - (Age at the time of death)

= (x-y)

= 29y {from equation-2}

= 29 x 64 {from equation-3}

= 1856

Now,

The age of the man in the year 1900

= 1900 - (year of birth)

= 1900 - 1856

= 44 years

Hence, the age of the man in the year 1900 is equal to 44 years.