x P(x) 0 0.25 1 0.15 2 0.05 3 0.55 Find the mean of this probability distribution. Round your answer to one decimal place.

Given:

The probability distribution table:

x     :      0               1               2                3

p(x) :   0.25         0.15          0.05          0.55

To find:

The mean of this probability distribution.

Solution:

The formula for mean of a probability distribution is:

Using this formula, we get

Therefore, the mean of this probability distribution is 1.9.

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15