(68 + 82 + 87 + 89 + x) / 5 > = 80
(326 + x) / 5 > = 80
326 + x > = 80 * 5
326 + x > = 400
x > = 400 - 326
x > = 74.......u would have to make at least a 74 to earn a B
what that person said.........;
Answer:

Step-by-step explanation:
Let's solve this problem step-by-step. The library had 1,500 books in 2011. The ratio of books in 2011 and in 2012 is 1:2. Therefore, let the number of books in 2012 be
.
We have the following proportion:

Therefore, there were 3,000 books in 2012. The ratio of books in 2012 and in 2013 is 2:5. Let the number of books in 2013 be
.
We have:

Therefore, there were 7,500 books in 2013.
Answer:
so sorry
Step-by-step explanation:
wish I could help but I don't know how to do it