My 6 year old daughter was complaining that she has filled up the piece of paper given for her maths homework,, so I thought I'd have a look.
Intuitively I thought that given 10 coins of which there are eight possible denominations (1p,2p,5p,10p,20p,50p,£1,£2) there may be quite a lot of possible combinations, so I thought the best way to check this was to knock up a Python script.
That spat out 19,448 combinations.
So I tried to refresh my maths knowledge (okay I Googled it) and came up with the formula:
(n+r-1)! / r!(n-1)! which if I plug in n=8 and r=10 also gives me 19,448 combinations.
I'm wondering if the correct response is to:
a) Buy several boxes of paper of my daughter to write out all the combinations
b) Teach her about factorials and combinations over the Easter break
c) Give up in despair