

.................................................
Answer:
A. The mean is increased by 3
Step-by-step explanation:
2 + 9 + 11 + 10 + 3 + 5 + 4 + 12 = 56/8 = 7
2 + 9 + 11 + 10 + 3 + 5 + 4 + 12 + 34 = 90/9 = 10
10 - 7 = 3
2x²-5x-3 = 0
(2x+1) (x-3) = 0
2x+1 = 0
2x = -1
x = -½
x-3 = 0
x = 3
then x = -½ , x= 3
76 -55= 21
76 is decreased by 21.
We initially start with 76, so now we have to divide 21 by 76:
21/76* 100%= 27.63%
Rounded to the nearest tenth, the final answer is 27.6%~
You can wright them as fractions reduce them and then compare them