Minutes are equal to 1/60ths and seconds are equal to 1/3600ths so
-128+30/60+45/3600
-128.5125
-128.513° (to nearest one-thousandth of a degree)
2.1234492726349426935739 or any number with a really long decimal which cannot be turnt into a simple fraction
Did you ever get the answer?
The answer would be -21.6
You're looking for a value

such that

Because the distribution is symmetric, the value of

in either case will be the same.
Now, because the distribution is continuous, you have that

The mean for the standard normal distribution is

, and because the distribution is symmetric about its mean, it follows that

.

You can consult a

score table to find the corresponding score for this probability. It turns out to be

.