Answer:
-1.540
Step-by-step explanation:
H0 : μ = 18
H0 : μ ≠ 18
The sample size, n = 48
Sample mean, xbar = 17
Sample standard deviation, s = 4.5
α = 0.05
The test statistic :
(xbar - μ) ÷ (s/√(n))
(17 - 18) ÷ (4.5 / √48))
-1 ÷ 0.6495190
= -1.5396
= -1.540 (3 decimal places ).
