This** preview**
has intentionally

**sections.**

*blurred***to view the full version.**

*Sign up*
**Unformatted text preview: **A") D
e ion. excel. chihmcfil‘eb er Q
set 68 D0 in ‘iCimlm 0i V,CPU (1005 9‘3 Inference about a variance Requiredconditions: Rmndom (001mm? GlPProx, ﬂﬂjmmj dl‘ﬂlilbuuon NM” .
Ho: 02 = 02° H3: (52 > 020 Reject Ho if: x2 > Xza,df H3: 02 < 020 Reject Ho if: x2 < X21-a,dr ..
H3: 02 at 02° Reject Ho if: x2 > qu/ur orx < x 1-(0/2),df 4,;— Degrees of freedom 2 n " l Gamay? _ ZL/v ii h “(9)02 _ z -1 2 Test statistic: x2 = (n :35 0‘ Confidence interval: (“2 1k < o2 < (:1 )3
0'0 xa/m; X149.” Ex: A sample of 10 extracted teeth bonded with a new type of adhesive resulted in the
following breaking strengths (after 24 hrs):
5.27 4.89 4.99 5.23 5.1 5.08 4.72 5.44 4.96 5.15 - Mpa A. Can the manufacturer conclude that the breaking strength variance of the new adhesive is less than the variance of the standard adhesive currently being used, which is .05, at the 5%
significance level? I, H0301=.05 Hm: 0': ¢ .05
1 x Olg‘BJq Ens—u— amen ' j a: _ z m
’5‘ X @010) 9 5| )(-0‘Dl : (’38
E o u
“i. Th6”? l9 “01 Chou >
of me new mdh iii evidence to conclude the, vmumno WC ifo leer, illO’lh inc vmria a
:25 gamma adhcmvc ounﬁmig bcmg used ohf B. Construct a 95% confidence interval for the variance of the breaking strength of the new
adhesive. Interpret your answer. - _. ...

View
Full Document

- Spring '13
- Leffakis
- Statistics, Normal Distribution, Statistical hypothesis testing, NM, Reject Ho