Hey there! I'm happy to help!
Whenever you see the word net used as an adjective like "net gain" or "net profit" it's basically how much you have of something with both the additions and subtractions. A normal profit would just be each sale you made but the net profit would be your sales minus the costs of making the stuff, taxes, liabilities, etc.
So, in our problem, the net gain is all of the points we got minus the points it lost.
So, we have a -7, -1, then a +13.
So, we have a +13. This is our gain. Then, we have 8 points we lost on the first two days, so we do 13-8, so we have a net gain of five.
However, we do not have a net gain of five as an answer option. Therefore, there must be a typo. The most obvious one I see is that when they say "then another 1 points on Tuesday", they might have meant there was one added, not subtracted. Therefore, we would only lose six points during the first two days, not eight.
13-6=7
In that case, the net gain is seven points, so we will go with this answer. We have a net gain of 7 points.
Have a wonderful day! :D
