In: Statistics and Probability
The figure below shows a frequency and relative-frequency distribution for the heights of female students attending a college. Records show that the mean height of these students is
64.564.5
inches and that the standard deviation is
1.81.8
inches. Use the given information to complete parts (a) through (c).
|
Height (in.) |
Frequency f |
Relative freq. |
|
|---|---|---|---|
|
60dash–under 61 |
22 |
0.00680.0068 |
|
|
61dash–under 62 |
66 |
0.02050.0205 |
|
|
62dash–under 63 |
2929 |
0.09900.0990 |
|
|
63dash–under 64 |
6565 |
0.22180.2218 |
|
|
64dash–under 65 |
9191 |
0.31060.3106 |
|
|
65dash–under 66 |
6969 |
0.23550.2355 |
|
|
66dash–under 67 |
2222 |
0.07510.0751 |
|
|
67dash–under 68 |
66 |
0.02050.0205 |
|
|
68dash–under 69 |
33 |
0.01020.0102 |
|
|
293293 |
1.0000 |
a. The area under the normal curve with parameters
mu equals 64.5μ=64.5
and
sigma equals 1.8σ=1.8
that lies to the left of
6464
is
0.39470.3947.
Use this information to estimate the percent of female students who are shorter than
6464
inches.
nothing%
(Type an integer or a decimal. Do not round.)
We have given
= 64.5 , standard
deviation
= 1.8
And we have also given
The area under the normal curve with parameters μ=64.5 and sigma σ=1.8 that lies to the left of 64 is 0.3947
That is P(x < 64) = 0.3947
And now we have asked to find the percent of female students who are shorter than 64 inches that is x<64
We have given that P( x < 64) = 0.3947 by multiplying this by 100 we get the percentage of female students who are shorter than 64.
Hence the percentage of female students who are shorter than 64 is= 0.3947 * 100 = 39.47 %
the percentage of female students who are shorter than 64 is 39.47 %
Hope this will help you. Thank you :)