What problem can be solved by using this multiplication 2/3x3/5

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.

Madeline takes her family on a boat ride. going through york canal, she drives 6 miles in 10 minutes. later on as she crosses stover lake, she drives 30 minutes at the same average speed. which statement about the distances is true?

Which statement is true about a number and its additive inverse? a. their product is always one. b. their sum is always one. c. they are always reciprocals of each other. d. their sum is always zero.