Credit crunch

Hand holding a blue bank card horizontally lengthways as if it is about to be put into an automated teller machine (ATM).


David's Personal Identification Number (PIN) is a 4-digit square number. How many possibilities are there?

Jessie's bank allows her to choose her own 4-digit PIN. How many choices does she have?

However, Jessie's bank does not allow the first digit of a PIN to be zero. How many choices does she now have?

Download image

Maths Eyes Australia logo Join in the fun on our Maths Eyes Australia Facebook page for teachers.