Compute the mean and variance of the following probability distribution. (Round your answers to 2 decimal places.) xP(x) 3.10 11.30 19.20 27.40

69.76

Step-by-step explanation:

The mean is the average of the numbers. It can be gotten by adding all the numbers, then divide by how many numbers available.

Variance (σ2) measure the spread between numbers in a data set. That is, it measures how far each number in the set is from the mean .

mean value can be computed using below expression

= ∑x(i)P(x(i))

= 3(0.10)+11(0.30)+19(0.20)+27(0.40)

= 18.2

Therefore, the mean value is 18.2

The variance can be calculated using below expression

variance

= ∑(x(i)-mean)^2 P(x(i))

= (3-18.2)^2 (.10) + (11-18.2)^2 (.30) + (19-18.2)^2 (.20)+(27-18.2)^2(0.40)

= 69.76

Therefore, the variance Vale is 69.76

b. 2

step-by-step explanation:

the slope of a line =δy/δx

δy= y₂-y₁

δx= x₂-x₁

therefore, using the points (-2,-3)   and (3,7) we can calculate gradient as follows:

m=(7--3)/(3--2) (a number minus a negative number the sign changes to a plus)

m=(7+10)/(3+2)

=10/5

=2

step-by-step explanation: where's the phrase?