Hi there!
Let r be the number of matches that Rebecca's team won.
We know that Katheryn's team won 9 more matches than Rebecca's team, and we know that Katheryn's team won 52 matches.
Using this given information, we can create the following equation.

If you wish to solve this, we can subtract both sides by 9 to get the following value for r.

Have an awesome day! :)
~collinjun0827, Junior Moderator
Since the number of days in July and in August is the same, there is no need to work out on the total number per month.
The mean number of people per day in August = 160 + 20 = 180
Answer: 180