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 [tex]a=\frac{4x+7}{2} \\b=\frac{5x+6}{2} \\c=\frac{3x+11}{2}[/tex]
Let us calculate sum of a,b,c in terms of x
a+b+c = [tex]\frac{4x+7+5x+6+3x+11}{2} \\=6x+12[/tex]
Average = sum/3 = [tex]\frac{6x+12}{3} =2x+4[/tex]
