posted by Tom 6 on .
The middle 69% of a normally distributed population lies between what two standard scores? (Give your answers correct to two decimal places.)0.31 and 1.69 was my answers and they are wrong????. .
You want the Z values containing 69%. Those are -1 <=Z <= 1
(well, 1.015, really)
that is, within 1 std of the mean.