The variance is the total of the squared distances of the given data from the mean.
This can be calculated through the equation,
σ² = summation of X² / N - μ²
where σ² is the variance X's are the data, N is the number of terms, and μ is the mean.
summation of X² = 100² + 100² + 120² + 120² + 180² = 81200
N = 5
μ = (100 + 100 + 120 + 120 + 180) / 5
μ = 124
Substituting these values to the equation for variance,
σ² = (81200/5) - 124² = 864
Thus, the variance is equal to 864.
Answer:
x = 1
y = -3
Step-by-step explanation:
if y = x - 4
then reorganise the first equation
4 (x - 4) = 9x -21
4x - 16 = 9x - 21
5 = 5x
x = 1
Answer:
96
Step-by-step explanation: