10
It depends on which country's currency the question is about.
Assuming that you are only using current US coins (5, 10, 25 and 50 cents), the answer is 21. NickelsDimesQuartersHalves1500013100112009300740055003600170010010811062104310241005105020312012205001310112010011
There are 47 ways using 5p, 10p, 20p and 50p.
3
22 ways
51
Three different ways.
120 different ways.
Two ways only: one with a pasta maker. The other using a rolling pin.
9=10
Three: one using only nickels, one using only dimes and one using only quarters!
Using only positive digits, and disregarding their order, 3 ways.