Answer:
Step-by-step explanation:
Let x = number of books that Hannah donated
We know that the number of students is 150 and the total number of books is represented by b, we can write that as:
Average number of books donated by each student = 
Now we know that Hannah donated 3 times as much as the average. We can write that as:
12h + 30w.....where h = hrs worked and w = wagons sold
so if an employee works 6 hrs and sells 3 wagons....then h = 6 and w = 3
12h + 30w
12(6) + 30(3) =
72 + 90 = $ 162 <==
It is decreased by a factor of 3. You can determine this by realizing that one inch original equals 3.3 feet, but the equals 1.1 feet, and 3.3/1.1 = 3.
(12 - 9) / 12 = (40 - x) / 40
3/12 = (40 - x) / 40
40(1/4) = 40 - x
10 = 40 - x
10 - 40 = -x
-30 = -x
30 = x <=== percent decrease from 40 to 30
