Henry Ernest Dudeney/Puzzles and Curious Problems/54 - The Birth of Boadicea/Solution

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Puzzles and Curious Problems by Henry Ernest Dudeney: $54$

The Birth of Boadicea
Boadicea died $129$ years after Cleopatra was born.
Their united ages (that is, the combined years of their complete lives) were $100$ years.
Cleopatra died $\text {30}$ $\text {BCE}$.
When was Boadicea born?


Solution

She was born in $\text {1}$ $\text {BCE}$.


Proof

Let $C_b$, $C_d$, $B_b$, $B_d$ denote the years of birth and death of Cleopatra and Boadicea respectively.

We have:

\(\ds B_d - C_b\) \(=\) \(\ds 129\) Boadicea died $129$ years after Cleopatra was born.
\(\ds \paren {B_d - B_b} + \paren {C_d - C_b}\) \(=\) \(\ds 100\) Their united ages (that is, the combined years of their complete lives) were $100$ years.
\(\ds C_d\) \(=\) \(\ds -30\) Cleopatra died $\text {30}$ $\text {BCE}$.
\(\ds \leadsto \ \ \) \(\ds 129 - B_p - 30\) \(=\) \(\ds 100\)
\(\ds \leadsto \ \ \) \(\ds B_p\) \(=\) \(\ds -1\)

$\blacksquare$


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