Question

Year	Average Length (sec)	Standard Deviation	n
1988	245.35	35.01	200
2008	234.60	45.60	200

I test the claim that the average song length was different in these two years by conducting a t-test. What p-value should I get?

a)0.0044

b)0.061

c)0.0088

d)0.99

Answer 1

The null and alternative hypothesis is,

The test is two-tailed test.

Now , assume that the population varinaces are not equals.

Therefore , use t-distribution.

The degrees of freedom is given by ,

The test statistic is ,

Therefore , the p-value is ,

p-value= ; The Excel function is , =TDIST(2.6444,373,2)