It will have 2 solutions because, if you take out the (-) it will be a whole diffrent answer!
Answer:
a. 0.71
b. 0.9863
Step-by-step explanation:
a. The mean of the distribution is given as $403,000 and the standard deviation is $278,000.
-To estimate the probability that a randomly selected house has a value less than $500,000:

Thus, the probability that a randomly selected house has a value less than $500,000 is 0.71
b. -since 40 is larger than or equal to 30, we assume normal distribution.
-The probability can therefore be calculated as:

Hence, the probability that the mean value of the 40 houses is less than $500,000 is 0.9863
Distribution is the way I learned it.
The complimentary event is the probability of it not raining. The probability of that is 1-2/5 = 3/5.
If you mean (1/9)^2, you square top and bottom as 1/9(1/9) = 1/81