Answer:
(a) = 40%
(b) = 28%
(c) Expected value = $222,500
Standard deviation = $7,216.88
Step-by-step explanation:
This is a normal distribution with a = 210,000 and b =235,000
(a) The probability that he will get at least $225,000 for the house is:
[tex]P(X\geq 225,000) =1 -\frac{225,000-a}{b-a} =1-\frac{225,000-210,000}{235,000-210,000} \\P(X\geq 225,000) =0.4= 40\%[/tex]
(b)The probability he will get less than $217,000 is:
[tex]P(X\leq 217,000) =\frac{217,000-a}{b-a} =\frac{217,000-210,000}{235,000-210,000} \\P(X\leq 217,000) =0.28= 28\%[/tex]
(c) The expected value (E) and the standard deviation (S) are:
[tex]E=\frac{a+b}{2}=\frac{210,000+235,000}{2}\\ E=\$222,500\\S=\frac{b-a}{\sqrt{12}}=\frac{235,000-210,000}{\sqrt{12}}\\S=\$7,216.88[/tex]