Answer:
The standard deviation of the following data set is 32.2
Step-by-step explanation:
step 1
Find the mean
we have
![[56,78,123,34,67,9,20]](https://tex.z-dn.net/?f=%5B56%2C78%2C123%2C34%2C67%2C9%2C20%5D)
Sum the data and divided by the number of elements
![[56+78+123+34+67+91+20]/7=469/7=67](https://tex.z-dn.net/?f=%5B56%2B78%2B123%2B34%2B67%2B91%2B20%5D%2F7%3D469%2F7%3D67)
step 2
For each number: subtract the Mean and square the result
![[(56-67)^{2},(78-67)^{2},(123-67)^{2},(34-67)^{2},(67-67)^{2},(91-67)^{2},(20-67)^{2}]](https://tex.z-dn.net/?f=%5B%2856-67%29%5E%7B2%7D%2C%2878-67%29%5E%7B2%7D%2C%28123-67%29%5E%7B2%7D%2C%2834-67%29%5E%7B2%7D%2C%2867-67%29%5E%7B2%7D%2C%2891-67%29%5E%7B2%7D%2C%2820-67%29%5E%7B2%7D%5D)
![[121,121,3,136,1,089,0,576,2,209]](https://tex.z-dn.net/?f=%5B121%2C121%2C3%2C136%2C1%2C089%2C0%2C576%2C2%2C209%5D)
step 3
Work out the mean of those squared differences
![[121+121+3,136+1,089+0+576+2,209]/7=1,036](https://tex.z-dn.net/?f=%5B121%2B121%2B3%2C136%2B1%2C089%2B0%2B576%2B2%2C209%5D%2F7%3D1%2C036)
This value is called the "Variance"
step 4
Take the square root of the variance
Answer:
area= 59.5 perimeter=31.6
Step-by-step explanation:
the area of the square is 49 because 7x7=49 and the area of the triangle is 3x7/2 because it is half of a rectangle so it is 10.5 + 49 = 59.5 and perimeter you add all the sides so 3+7.6+7+7+7= 31.6
A whole number is always written as itself over one.
45/1
Answer: 45/1
Answer: x=4,-4 Solve the equation for x by finding a, b, and c of the quadratic then applying the quadratic formula
