Bilbo has a gold chain with 20 links. He is staying in town for 20 days at an inn and wishes to pay each day with one gold link. When he cuts the chain, the remaining links looks like the diagram below: The diagram shows 10 links but there are 20 on Bilbo’s chain. If […]

# Permuatations&Combinations

# Permutation example

[caption id="attachment_183" align="alignnone" width="209" caption="There are 7 digits 0,1,2,3,5,7,8 ( repetition not allowed), Find how many 5 digit EVEN numbers can be formed ? "][/caption]