Answer:
583
Step-by-step explanation:
The mean of a data set is the average of the data set. It can be found by adding up all of the values and then dividing by the total number of values added. In this case, one is given the mean, and one needs to find a missing value. Since there is a missing element, add one to the total number of values in the data set. The missing element is represented by the parameter (x). Set up an equation and solve:

Simplify,

Inverse operations,

Answer:
3:1
Step-by-step explanation:
&%6#46+4636$7$-&&%$44
Answer: $ 2.20
Step-by-step explanation: 31.80-18.60= 13.20
13.20 divided by 6= 2.20
——————-
2.20 x 6= 13.2
13.20+ 18.60= 31.80
Answer:
x = 19
Step-by-step explanation:
123°+3x = 180°
3x = 180°-123°
3x = 57
x = 57/3
x = 19
The reason why we use 123° + 3x = 180° because both are adjacent angles. Adjacent angles add up to 180°
You can do this fairly easily on Excel. (its 56)