Let \(c\) be the number of children; \(m\) be the number of men and \(w\) be the number of women

\(c + m + w = 316\)

\(c = 78 + w\)

\(w = 56 +m\)

\(78+56+m + 56+m +m = 316\)

\(190 +3m = 316\)

\(m = 42\)

**Answer:** There are 42 men watching a movie