Each of 12 refrigerators of a certain type has been returned to a distributor because of an audible, highpitched, oscillating noise when the refrigerators are running. Suppose that 7 of these refrigerators have a defective compressor and the other 5 have less serious problems. If the refrigerators are examined in random order, let X be the number among the first 6 examined that have a defective compressor. What is the probability that X exceeds its mean valueby more than 1 standard deviation?

0.121

Step-by-step explanation:

From the given information:

Let X be a hypergeometric random variable. i.e X h (x;:6,7,12)

To determine the mean and the standard deviation of X of a hypergeometric random variable; we have:

The standard deviation is :

However, the inequality for the event showcasing how X exceeds its mean value by more than 1 standard deviation is :

∴

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

source:

i would need to see the dot plot : )