We’ve established that heights of 10-year-old boys vary according to a Normal distribution with μ = 140 cm and σ = 5 cm.
What proportion is between 150 and 140 cm?
a. |
68% |
|
b. |
50% |
|
c. |
97.72% |
|
d. |
47.72% |
Solution :
Given that ,
mean = = 140
standard deviation = = 5
P(140< x <150 ) = P[(140 - 140) / 5< (x - ) / < (150 - 140) / 5)]
= P( 0< Z < 2)
= P(Z < 2) - P(Z < 0)
Using z table
= 0.9772 - 0.5
=0.4772
=47.72%
We’ve established that heights of 10-year-old boys vary according to a Normal distribution with μ =...
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