If the absolute value of the t Stat is greater than the t Critical 2 tail
value, it means there is a significant difference of the populations.

"Anita" wrote:

Hello

I have a support call to do for one of my customers. He is using a function
called Ttest. Unfortunately I have no knowledge on statistics so I don't
even know what a ttest is ! The formula result has E-15 after it and he
wants to know what that means and whether it is normal? He also wants to
calculate probability. Does this make any sense to anyone? I can provide
more info. if need be.

The version is 2000.

Many thanks

Anita