Question

Which is the mode of this data set?

55, 78, 43, 39, 78, 61, 75, 50, 43, 78

Answer 1

The mode of a data set is the most appearing number. I like to order the numbers ascending, or getting bigger, to make it easier:
39, 43, 43, 50, 55, 61, 75, 78, 78, 78

It is clear that the mode is 78.

Answer 2

the mode is number 78