A lecture wanted to compare his teaching methods towards 2 different class. The first class, he took 10 students randomly while the second class he took 8 students randomly as well and note it as below:

N1 N2 N3 N4 N5 N6 N7 N8 N9 N10
Class 1 77 74 49 68 86 80 71 77 81 72
Class 2 78 57 65 82 73 76 54 56 - -

Hypothesis

$$ H_0 : \mu1 = \mu2

$$

$$ H_1 : \mu \neq \mu2 $$

Formula

$$ t = \frac{\bar{x_1}-\bar{x_2}}{S_p\sqrt{\frac{1}{n_1}+\frac{1}{n_2}}} $$

$$ DF=n_1 +n_2-2 $$

$$ S_p=\sqrt{\frac{(n_1-1)S_1^2+(n_2-1)S_2^2}{n_1+n_2-2}} $$