I have four different sweaters. Every day I choose one of the four sweaters at random to wear. Let X be the number of different sweaters I wore during a 5-day week.

(For example, if my 5-day sweater sequence is 3,2,4,4,2 then X = 3 because that week I wore sweaters {2,3.4}.)

Find the mean of X.

Mean is 6

Step-by-step explanation:

Mean refers to the average of the observations.

Let X be the number of different sweaters I wore during a 5-day week.

Possible values of X = 1, 2, 3, 4

For X = 1,

For X = 2,

For X = 3,

For X = 4,

To find: Mean

Solution:

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2