We laughed greatly at a pretty jest on the part of Major Trenchard, a merry friend of the Squire's. 
With a piece of chalk he marked a different number on the backs of eight lads who were at the party.

Then, it seems, he divided them in two groups, as shown in the illustration, 1, 2, 3, 4 being on one side, and 5, 7, 8, 9 on the other. It will be seen that the numbers of the left-hand group add up to 10, while the numbers in the other group add up to 29. 

The Major's puzzle was to rearrange the eight boys in two new groups, so that the four numbers in each group should add up alike.

The Squire's niece asked if the 5 should not be a 6; but the Major explained that the numbers were quite correct if properly regarded.

See answer