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x = 0.0508 6
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(x x ) 2 (0.051 0.0508) 2 + (0.0505 0.0508) 2 + etc...
2
s
=
=
= 9.15 107 7
4,48=
6
n
1
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4,495:
s = s2 = 9.56 104
9
4,496
:
4,494<
;
4,494:
"-!""!"!+ t
=
x μ0 0.0508 0.05
=
= 2.17 " ! >;-5>:
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""# ) t
=
x1 x 2
x1 x 2
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2
2
1
1
s
s
1
2
s2 + + n
n
n
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1
2
2
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!#!& *
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=
x1 x 2
s12 s22 + n1 n 2 =
700 668
212 30 2
+
12
6
= 2.342 ;.1+1/:.2+1/;.12+1/:.6+1/;16
!!+ !"!!'!+#" !$0*010*02' $!0* !!
! ! ! *
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60
55
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"
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" 155*25
51*75
51*75
17*25
2 = (O E) 2 (143 155.25) 2 (60 51.75) 2 (55 51.75) 2 (18 17.25) 2
=
+
+
+
= 2.519 E
155.25
51.75
51.75
17.25
<5,2<4
!##3!#%$")#,%$"!#!#1+36)"#"!#!$!!#(
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$"!" $!+ !#$"!%%$"!3)5)5)4)4)4)3)4)2)"#3"##"#"*
2 = (2 2.778) 2 (3 2.778) 2 (4 2.778) 2 (O E) 2 (1 2.778) 2
=
+ 2
+ 4
+ 2
= 2.72 E
2.778
2.778 2.778 2.778 <:,2<9
!##3!#%$")#,%$"!#!#1+36)"&#!#1+ $""(
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#1 +# 3
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#1 +# 3
+ $")#'#%$"*
( #1 +# 2 )
#1 +# 2 +# 3 +# 4 E=
(#1 +# 3 )(#1 +# 2 ) (row total)(column total) =
grand total
#1 +# 2 +# 3 +# 4
!"!<.,2/.,2/ &!"#$!!&""#$!$"
2
," $!"##"#""# 2 = (O E) E
#,%$"!##3!#%$"+
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224
224
221
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246
283
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97
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292
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641
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5:2
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,&! &! %" # '%# &
E=
(row total)(column total) (495)(490)
=
= 123.75 grand total
1960
!
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7-, $
2 = !
"
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-./'31 -.0
-.0'.2
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-10'/-
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35'31
35'5-
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(O E) 2 (113 123.75) 2 (113 124) 2 (110 124.26) 2
=
+
+
+ etc... = 91.73 E
123.75
124
124.26
6*(-+*(-+6*0(-+*0(-+65
. ! %(! ,',,-%", "! '
$ $
$ $
$! P(A and B) = P(A) P(B) "! $!! P(A or B) = P(A) + P(B) P(A and B) $! ! ! P(A | B) =
P(A and B)
P(B)
P(A | B) =
P(B | A) P(A)
P(B)
&
$ $ $"" '" ' "($ "$ ($" !' $' $ ! $)
$
" "
0.5 0.5 0.5 = 0.125 = P(A and B) = P(2 children = bb and 1st child bb) $
" . % P(B) = P(1st child = bb) = 0.5 P(A and B) 0.125
$ P(2 children = bb | 1st child bb) = P(A | B) =
=
0.25 P(B)
0.5
"$ 1-2 # /-2 !' $ #& "$ " #(
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P(A | B) =
P(B | A) P(A)
P(B)
P(S = Z |W = Zz) = 0.5 +0-2 ,
P(W = Zz) = 0.7 +,
P(S = Z) = (0.7 0.5) + (0.3 1) = 0.65 + #
0.5 0.7
P(W = Zz | S = Z) =
= 0.538 0.65
" m
P(X = m) =
,
$" "
(nm )
n! p (1 p)
m!(n m)!
3
" " "(
P(1 boy of 5 children) =
5!0.51 0.5 4
= 0.15625 1!(4)!
$ "&
&
P(X = m) =
enp (n p) m
m!
% ! 
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