What are the combinations of the numbers 5 6 7?

Answer 1

How many digits are in each combination ? ?

-- If one, then there are three combinations: {5}, {6}, and {7) .

-- If two, then there are three combinations: {5, 6}, (5, 7), and {6, 7}.

-- If three, then there is only one combination: {5, 6, 7}