Question

A researcher is interested in the relationship between oral contraceptive (OC)
use and blood pressure in women. Suppose a sample of ten 35-to 39 year old
nonpregnant, premenopausal OC users who work in a company and have a mean
systolic blood pressure (SBP) of 132.86 mm Hg and sample standard deviation
of 15.34 mm Hg are identified. A sample of 21 nonpregnant, premenopausal,
non-OC users in the same age group are similarly identified who have mean
SBP of 127. 44 mm Hg and a sample standard deviation of 18.23 mm Hg. A
researcher assumes that the two groups are independent and normal will equal
variances.
1. Using the p-value, does the underlying mean difference in blood pressure
between the two groups differ from zero? Use the significance level =
0.05.
2. Compute a 95% confidence interval for the true mean difference in systolic
blood pressure (SBP) between 35 to 39 year old OC users and non-OC
users. Interpret this result.

Answer 1

TEXAS INSTRUMENTS TI-83 Plus 2-SaMPTTest 11.Z t=.8114533413 p=.423715799 df=29 X1=132.86 X2=127.44 STAT PLOT F1 TBLSET F2 FORMAT F3 CALC F4 TABLE F5 Y= WINDOW ZOOM TRACE GRAPH QUIT INS 2nd MODE DEL A-LOCK LINK LIST ALPHA X,1,0,n STAT TEST A ANGLE B DRAW C DISTR MATH APPS PRGM VARS CLEAR MATRIX D SIN-1 E cos-1 F TAN-1 GT H SIN COS TAN X-1 EE K } e M 72 7 ) 을 10X Nu PW Q[ R LOG 7 8 9 х et S L4 TL5 U L6 V] w LN 4 5 6 RCL X L1 Y L2 Z L3 ө МЕМ STO 1 2 3 + OFF ? ENTRY SOLVE CATALOG í 0 ANS (-) ON ENTER