Welcometsack !

. Exam 2 Wednesday April 3rd 7- 8:30PM

7.4,

8. I - 8.3,

9. I -9.5

Makeup ? Forns/uEJ 3/26 ! ! !

aHW 8.3 due 3124

PDFs and CDFSIft ) -_ fjpcxidx-

PDF- i ) 1in IA ) = O

+ → - a

pix)Ex,elfin .IM ' I

t 3) I' At = pet )

1) PHILO median T

2) Sdpcxidx -1meant -

- a µ=f!xpMdx §pmdx=tz

Normatlistrioution C Bell Carne or Gaussian )

µ- mean

suppose

G - standard deviationµ

-

-

15pan

pan-

. ÷ ,

e"at 6=1

a-

§! pan dx=12131415161718 -

Note ! mean = M

AGENT? EQUALS µ! 954C

KID9990

Pr ( a ex Elo ) = S! pcxldx

Exe : The rain fall in Anchorage Alaska can be modeled

by a normaldistriout.in with

µ=Einches

and standard deviation inch.

what fraction of

years is the rainfall a) greater than 17 inches

lol between 15 and 17 inches

a) §÷r*.

e-"

dx= 5,5¥.

e-'

oh,

§"

¥ ,

E " 'Ix a o.

02275Either will do

.

5,25.to,

e-"d× a 0.02275

b) Sista e-'

oh,a 0.4772 picture

0.47725 Calculator

Exe : IQ scores can be modeled by a normal distribution

with mean 100 and standard deviation 15.

what fraction of the population has an IQ between

105 and 120 ?

µ= 100 G = 15

€#§! .EE#e-%EfITdx =0.27823 . .

Examples of Normal Distributions-

Coin tosses