The ratio of girls to boys at a movie is 3:8. If there are 32 boys, how many girls are at the movie

Answer: 12 girls

Step-by-step explanation: Our first step in this problem is to write down the unit ratio that is involved. In this case, it's girls/boys.

Next, we set up our proportion. We know that at a movie there are 3 girls for every 8 boys so we have 3/8 and we are asked how many girls are at the movie if 32 boys are the movie so that's x/32.

Now we have the proportion 3/8 = x/32.

Notice that the 32 boys must go on the bottom of the second ratio because our unit ratio tells us that we put girls/boys.

Solving from here, we use the means-extremes property to get 3 times 32 to get 96 = 8 times x or 8x. So we have 96 = 8x.

Dividing both sides by 8, we find that 12 = x.

This means that 12 girls are at the movie when 32 boys are at the movie.