40% of the people attending the movie were adults if 20 adults attended the movie then how many people attended the movie (use a ratio box)

50

Step-by-step explanation:

Let x represent the number of people that attended the movie.

And y the number of adults that attended the movie

Given;

Percent of adults that attended the movie = 40%

Number of adults that attended the movie y = 20

So,

40% of those that attended the movie area adults.

y = 40% of x

y = 40/100 × x

y = 0.4x

(Ratio of y to x is 4:10 or 0.4)

Making x the subject of formula;

x = y/0.4

Substituting the value of y given;

x = 20/0.4

x = 50

Therefore, 50 people attended the movie.