Henry Ernest Dudeney/Puzzles and Curious Problems/45 - Brother and Sister

Puzzles and Curious Problems by Henry Ernest Dudeney: $45$

Brother and Sister

A boy on being asked the age of himself and his sister replied:

"Three years ago I was seven times as old as my sister;

two years ago I was four times as old;

last year I was three times as old;

and this year I am two and one-half times as old."

What are their ages?

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Arithmetical and Algebraical Problems: Age and Kinship Puzzles: $45$. -- Brother and Sister
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Arithmetical and Algebraical Problems: Age Puzzles: $40$. Brother and Sister