Answer: z(p) = 1.9286 and we reject H₀
Step-by-step explanation:
1) According to problem ststement : We need to solve an Hypotesis test proportion so:
H₀ P₀ = 0,4 and Hₐ < 0,4 ( Alternative hipotesis)
From 700 employes 305 are determined to earn more than $ 50000
Proportion pₐ = 305/700 = 0,4357 pₐ = 0,4357
proportions are p = 0.4 and q = 0,6
We will asume a confidence level of 95 % hence α= 1-0,95 α = 0,05
so from z table we find z(c) = 1,64
Therefore we must calculate our z(p) = ( pₐ-p₀) ÷√(p*q)/n
Calculating z(p) = 0,0357 /0,01851 ⇒ z(p) 1.9286
Our test is one of the form Hₐ < ; that means is a right tail test, and the value z(p) is bigger than our critical value (z(c) = 1.64) so we rejecte H₀