Choose two digits and arrange them to make two double-digit
numbers. Now add your double-digit numbers. Now add your single
digit numbers. Divide your double-digit answer by your single-digit
answer. Try lots of examples. What happens? Can you explain it?
Can you create a Latin Square from multiples of a six digit number?
When asked how old she was, the teacher replied: My age in years is
not prime but odd and when reversed and added to my age you have a
The number 10112359550561797752808988764044943820224719 is
called a 'slippy number' because, when the last digit 9 is moved to
the front, the new number produced is the slippy number multiplied
Find slippy numbers ending in 4 (a small one) and in 2 and 3
Explain why the slippy number ending in 9 has a unique sequence
of digits; can there be more than one slippy number ending in
You might like to write a short program to find other slippy