What is the mean of -9,-5,-4,-4,-2,0,1,2,3,5

- 1.3

Step-by-step explanation: I believe that it's -1.3 if you're referring to the arithmetic mean.

(1) Take the sum of -9, -5, -4, -4, -2, 0, 1, 2, 3, 5 and simplify it to -13

(2) Count the number of terms in the data set.

{-9, -5, -4, -4, -2, 0, 1, 2, 3, 5}

{1, 2, 3, 4, 5, 6, 7, 8, 9, 10} - The number of terms in the data set is 10.  

(3) Divide the sum by the number of terms and simplify.

-13 / 10 = -1.3 (simplified)

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional