See the Wikipedia page for the t-test, what you want is about half way down (here)
CB
a.
Comparison of GPA for randomly chosen college juniors and seniors:
= 3.05, s1 = .20, n1 = 15, = 3.25, s2 = .30, n2 = 15, α = .025, left-tailed test.
b.
Comparison of average commute miles for randomly chosen students at two community colleges:
= 15, s1 = 5, n1 = 22, = 18, s2 = 7, n2 = 19, α = .05, two-tailed test.
c.
Comparison of credits at time of graduation for randomly chosen accounting and economics students:
= 139, s1 = 2.8, n1 = 12, = 137, s2 = 2.7, n2 = 17, α = .05, right-tailed test.
Do a two-sample test for equality of means assuming unequal variances.
For A,B, and C find:
d.f.
Standard Error
t-calc
p-value
t-crit