Answer:
mean = 1 power failure
variance = 1 (power failure)²
Step-by-step explanation:
Since the mean is computed as
mean = E(x) = ∑ x * p(x) for all x
then for the random variable x=power failures , we have
mean = ∑ x * p(x) = 0 * 0.4 + 1* 0.3 + 2*0.2 + 3* 0.1 = 1 power failure
since the variance can be calculated through
variance = ∑[x-E(x)]² * p(x) for all x
but easily in this way
variance = E(x²) - [E(x)]² , then
E(x²) = ∑ x² * p(x) = 0² * 0.4 + 1²* 0.3 + 2²*0.2 + 3²* 0.1 = 2 power failure²
then
variance = 2 power failure² - (1 power failure)² = 1 power failure²
therefore
mean = 1 power failure
variance = 1 power failure²
Supplementary angles are angles that add up to 180 degrees.
180 = 3x + 4 + 8x + 11
Combine like terms.
180 = 11x + 15
Subtract 15 from both sides.
165 = 11x
Divide both sides by 11
15 = x
m<ABC = 3x + 4 = 3(15) + 4 = 45 + 4 = 49 degrees.
$67.50 for three pairs of pants. $97.50 for five pairs of jeans. For all of these the price would be $165.00
