Solve for X and show work

If the measure of xyz is 81 what is the measure of yz

At the newest animated movie, for every 9 children, there are 4 adults. there are a total of 39 children and adults at the movie.

How many of the 250 grandparents in the population would you expect to prefer online shopping with merchant a? merchant a: 4 merchant b: 6 merchant c: 2 merchant d: 3 other: 5 none: 5 answer choices: a.about 4 b.about 8 c.about 40 d.about 21