In order to estimate the statistical difference between the average hourly wages of employees of two branches of a department store, two independent random samples were selected and the following statistics were calculated. Downtown Store North Mall Store Sample size 25 20 Sample mean $9 $8 Sample standard deviation $2 $1 A 95% interval estimate for the difference between the two population means is _____. Group of answer choices

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Answer:

0.076 ; 1.924

Step-by-step explanation:

Given that :

_______Downtown Store ___ North Mall Store

n _______25 _______________20

Mean (m) _ $9 _______________$8

Sample sd_ $2 ______________$1

Standard Error (SE) = √[(s1²/n1) + (s2²/n2)]

√((2^2/25) + (1^2/20)) = 0.4582575

df = (25 + 20) - 2= 43

(m2 - m1) ± t(df = 43 , 0.025) * SE

(9 - 8) ± 2.01669 * 0.4583

(1 - 0.9242) ; (1 + 0.9242)

0.076 ; 1.924