My local greengrocer is a would-be mathematician.
They like to arrange their apples in nice rows.
However, when they lay their apples in rows of 3 they has one left over.
When they lay them in rows of 5 they also has one left over.
Remarkably they also have one left over when they arrange them in rows of 7 and 9.
11 seems to be the magic number, for, in rows of 11 there are no apples left over.
How many apples does the greengrocer have?