The average is pretty simple to find. Add up all the numbers, then divide by how many numbers there are. In other words it is the sum divided by the count.
The answer to this specific question can be modeled as
. After simplifying everything, you would get x
77, so Justin has to get at least a 77 to get a 75 average.
You bought 5 books for $60 and 2 movies for $30
7*9
b. 63
v=5 i=1
5+1+1= 7
x=10
10-1= 9
9*7= 63
0 is the answer! that is because 62 is also the mean.