Henry Ernest Dudeney/Modern Puzzles/54 - The Two Additions

Modern Puzzles by Henry Ernest Dudeney: $54$

The Two Additions

Can you arrange the following figures into two groups of $4$ figures each so that each group shall add to the same sum?

$1 \ 2 \ 3 \ 4 \ 5 \ 7 \ 8 \ 9$

If you were allowed to reverse the $9$ so as to change it into the missing $6$ it would be very easy.

For example, $1, 2, 7, 8$ and $3, 4, 5, 6$ add up to $18$ in both cases.

But you are not allowed to make any such reversal.

Sources

• 1926: Henry Ernest Dudeney: Modern Puzzles ... (previous) ... (next): Arithmetical and Algebraical Problems: Digital Puzzles: $54$. -- The Two Additions
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Arithmetical and Algebraical Problems: Digital Puzzles: $105$. The Two Additions