About 23% of people who get their eyes examined are found to have a detached retina (the retina is pulled away from the tissue at the back of the eye). What is the probability of an ophthalmologist examining seven people until he finds the first patient who has a detached retina?

Step-by-step explanation:

given that about 23% of people who get their eyes examined are found to have a detached retina (the retina is pulled away from the tissue at the back of the eye).

Each person coming for check up is independent of the other

Hence any person to have a detached retina has probability = 0.23 and each person is independent of the other

Prob for any person not to have detached retins = 0.77

The probability of an ophthalmologist examining seven people until he finds the first patient who has a detached retina

= Probability that first 6 persons did not have detached retina* prob 7th person has detached retina

= (since each person is independent of the other)

= 0.043937

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

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