Henry Ernest Dudeney/Modern Puzzles/Arithmetical and Algebraical Problems/Age and Kinship Puzzles
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Henry Ernest Dudeney: Modern Puzzles: Arithmetical and Algebraical Problems
$21$ - Their Ages
- If you add the square of Tom's age to the age of Mary,
- the sum is $62$;
- but if you add the square of Mary's age to the age of Tom,
- the result is $176$.
- Can you say what are the ages of Tom and Mary?
$22$ - Mrs. Wilson's Family
- Mrs. Wilson had three children, Edgar, James and John.
- Their combined ages were half of hers.
- Five years later, during which time Ethel was born, Mrs. Wilson's age equalled the total of all her children's ages.
- Ten years more have passed, Daisy appearing during that interval.
- At the latter event Edgar was as old as John and Ethel together.
- The combined ages of all the children are now double Mrs. Wilson's age, which is, in fact, only equal to that of Edgar and James together.
- Edgar's age also equals that of the two daughters.
- Can you find all their ages?
$23$ - De Morgan and Another
- Augustus de Morgan, the mathematician, who died in $1871$, used to boast that he was $x$ years old in the year $x^2$.
- My living friend, Jasper Jenkins, wishing to improve on this, tells me he was $a^2 + b^2$ in $a^4 + b^4$;
- that he was $2 m$ in the year $2 m^2$;
- and that he was $3 n$ years old in the year $3 n^4$.
- Can you give the years in which De Morgan and Jenkins were respectively born?
$24$ - "Simple" Arithmetic
- Two gentlemen with an eccentric approach to philosophy were pinned down by your investigative reporter.
- They wished to riddle my mathematical understanding.
- "Our two ages combined," said the first, "is $44$."
- "Don't be silly," said the other, "it's $1280$."
- They looked at me and said, "You see, we didn't tell you how we were combining them."
- It was clear to me that the first number was their difference and the second was their product.
- Now, how old were these two gentlemen?