Question

Two samples are taken with the following sample means, sizes, and standard deviations
¯x1x¯1 = 24 ¯x2x¯2 = 25
n1n1 = 65 n2n2 = 71
s1s1 = 4 s2s2 = 3

Estimate the difference in population means using a 88% confidence level. Use a calculator, and do NOT pool the sample variances. Round answers to the nearest hundredth.
< μ1−μ2μ1-μ2 <

Answer 1

Given that,

n₁= 65 , $\bar x_1 = 24$ and s₁ = 4

n₂ = 71, $\bar x_2 = 25$ and s₂ = 3

Using TI-84 calculator we get, 88% confidence interval for $\mu_1 -\mu_2$ is,

$-1.96 < \mu_1 -\mu_2 < -0.04$

TI-84 Plus TEXAS INSTRUMENTS 9563 -.2436 df=1 18 . 2233443 X 1 =24 ー2-25 STAT PLOT F1 TBLSET F2 FORMAT F3 CALC F4 TABLE F INDOw QUIT MODE LINK X,T,e,n ANGLE B APPS INS DEL LIST STAT DRAW 2ND A-LOCK ALPHA TEST A MATH MATRIX D C CLEAR VARS PRGM SIN COSFTAN G COS SIN TAN 10* N LOG e* S LN RCL X u o w Q V P 8 L5 U 5 7 9 L4 T LG V 4 6 MEM " STO L1 Y L2 Z L3 θ OFF ENTRY SOLVE 2 3 ON ENTER CATALOG ANS ? 0