800 * 100 = 80000
810 * 99 = 80190
900 * 90 = 81000
1000 * 80 = 80000
(800 + 10n) (100-1n)
=(800 +10(11)) (100 - 11)<span>
(910)(89) = 80990</span>
Answer:
C
Step-by-step explanation:
If x is the average (arithmetic mean) of m and 9, y is the average of 2m and 15, and z is the average of 3m and 18,
x=(m+9)/2
y=(2m+15)/2
z=(3m+18)/2
the average of x, y, and z
=(x+y+z)/3
=(m+9+2m+15+3m+18)/3
=(6m+42)/3
=2m+14
ans is C
I think it’s either C or D