Answer:
We reject H₀ the actual percentage of type A donations differs from 40%
Step-by-step explanation:
Sample information:
sample size n = 146
Type A x₁ = 81 and p₁ = 81 / 146 p₁ = 0,5547
then q₁ = 1 - p₁ q₁ = 1 - 0,5547 q₁ = 0,4453
We choose as significance level α = 5% α = 0,05 α /2 = 0,025
from z-table we find z (c) = 1,96
National % of the population ( μ = 40 % μ = 0,4 )
Test hypothesis
Null hypothesis H₀ p₁ = μ
Alternative Hypothesis Hₐ p₁ ≠ μ
The Alternative hypothesis indicates that the test is a two-tail test
z(s) = ( p₁ - μ )/ √ p₁*q₁ / n
z(s) = ( 0,5547 - 0,40 )/ √ 0,5547*0,4453 / 146
z(s) = 0,1547 / 0,041
z(s) = 3,77
Comparing z(s) and z(c)
z(s) > z(c)
z(s) is in the rejection region. We reject H₀. Sample does not give evidence to support that the actual percentage of type A donations is equal to the national population
