The hypotheses are as follows:
 Null hypothesis

H_{0}: μ_{1} – μ_{2} = 0 
The difference between the population means (μ_{1} – μ_{2}) equals 0. 
 Alternative hypothesis
 Select one of the following alternative hypotheses.
H_{1}: μ_{1}– μ_{2}≠ 0 
The difference between the population means (μ_{1} – μ_{2}) does not equal 0. 
H_{1}: μ_{1}– μ_{2}> 0 
The difference between the population means (μ_{1} – μ_{2}) is greater than 0. 
H_{1}: μ_{1}– μ_{2}< 0 
The difference between the population means (μ_{1} – μ_{2}) is less than 0. 