Regular Expression for Percentage of marks

I am trying to create a regex that matches percentage for marks

For example if we consider few percentages

1)100%
2)56.78%
3)56 78.90%
4)34.6789%

The matched percentages should be

100%
56.78%
34.6789%

I have made an expression "\\d.+[\\d]%" but it also matches for 56 78.90% which I don't want.

If anyone knows such expression please share