Henry Ernest Dudeney/Puzzles and Curious Problems/140 - A Curious Progression

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Puzzles and Curious Problems by Henry Ernest Dudeney: $140$

A Curious Progression
A correspondent sent this:
"An arithmetical progression is $10, 20, 30, 40, 50$, the five terms of which sum is $150$.
Find another progression of five terms, without fractions, which sum to $153$."


We noted at once the wily omission of a word in the last sentence,
because such an arithmetical progression is not possible.
We therefore suggested, by way of jest, this queer solution:
a progression of $5$ [then] current silver coins: $3 \oldpence$, $1 \shillings$, $2 \shillings$, $2 \shillings 6 \oldpence$, $4 \shillings$, $5 \shillings$,
which sum to $153$ pence.
But this is not his own answer, which is quite satisfying -- no algebraic complexities.
What is it?


Click here for solution

Sources