Answer:
2x+4
Step-by-step explanation:
Given that a is the average (arithmetic mean) of 4x and 7, b is the average of 5x and 6, and c is the average of 3x and 11
By definition of arithmetic mean,
we have 
Let us calculate sum of a,b,c in terms of x
a+b+c = 
Average = sum/3 = 
Answer:
D. y=30x
Step-by-step explanation:
So x represents like say if he mowed 3 yards.
y=30(3)
Then y would equal 90