What did I do wrong in the permutations question. I was given the following question:
A hardware store sells numerals for house numbers. It has large quantities of the numerals 3, 5, and 8 but no other numerals. How many different house numbers, with no more than three digits can be made from these numbers?
So, I tried to solve it by multiplying 3 x 3 x 3 = 27 because there were 3 choices at each step. However, according answers of this book the answer is 39 and not 27.
Please explain what I did wrong.
Thank you :)

You've worked out the number of house numbers with exactly $3$ digits, but the question says `no more than' $3$ digits.
See if you can work out the number of house numbers with only $2$ or $1 $ digit!
