What is the mean change with the numbers 90 91 88 84 86 85 86

-0.571428571, or - 0.6 if you round it to the nearest tenth

Step-by-step explanation:

Okay, so to break it down, you want to find the difference between each of the numbers right next to each other.

90 - > 91 = 1

91 - > 88 = - 3

88 - > 84 = - 4

84 - > 86 = 2

86 - > 85 = - 1

85 - > 86 = 1

Add up all the differences.

1 - 3 - 4 + 2 - 1 + 1 = - 4

How many numbers were there? 7

Divide the sum (-4) by 7.

-4/7 = - 0.571428571