Question

1. A jeepney driver claims that his average monthly income is Php 3000.00 with a standard deviation

of Php 300.00. A sample of 30 jeepney drivers were surveyed and found that their average monthly 

income is Php 3500.00 with a standard deviation of Php 350.00. Test the hypothesis at 1% level of 

significance

Answer 1

Solution:

Given, $\mu=3000,n=30,\sigma=350, \bar X=3500$

At 1% significance level and df=29, t=2.462021

$H_0:\mu=3000 \\H_1:\mu\ne3000$

Now, $\dfrac{\bar X-\mu}{\sigma/\sqrt n}=\dfrac{3500-3000}{350/\sqrt {30}}=7.824>2.462021$

$H_0$ is rejected.

Thus, $\mu\ne3000$