<h3>
Answer: 78.6</h3>
Work Shown:

Multiply across the rows to form a third column. Example: 9*90 = 810 in the first row.

The values in the third column add to 810+1440+1050 = 3300
Divide this over the total number of people which is 9+18+15 = 42
The mean is 3300/42 =78.571 approximately which rounds to 78.6
Answer:
unknown
Step-by-step explanation:
because you don't know the percentage one gallon takes you cannot be sure how much you need after you get the dimensions and percentage a gallon takes
Answer:
6
Step-by-step explanation:
Don't let the variable confuse you. Replace n with 9. Then, subtract 9 from 15.
Answer:
b
Step-by-step explanation:
I think it's SAS
It is because O is the common angle and the two sides are similar.