The random variable x represents the number of computers that families have along with the corresponding probabilities. find the mean and standard deviation for the random variable x.

The given data for this problem are as follows:
x         0           1           2           3         4 
p(x)   0.49     0.05     0.32     0.07     0.07

we are asked to get the mean of the random variable x

to get the mean, we use the formula
x̄  = σxp(x)
x̄ = 0(0.49) + 1(0.05) + 2(0.32) + 3(0.07) + 4(0.07) = 4.97

to get the standard deviation, we use the formula
σ =√[ ∑x²p(x) -   x̄ ]²
substituting
σ =  √[ (0²(0.49) + 1²(0.05) + 2²(0.32) + 3²(0.07) + 4²(0.07)) - 4.97]²
σ = 1.89

so, the mean is 4.97 and the standard deviation is 1.89