00:01
Alright, so this question asks us about the standard normal distribution, which you can see a rough sketch of here, centered at zero, and out to three standard deviations on either side.
00:11
So part a wants the probability that z is less than or equal to 1 .5, which is simply the area between negative infinity and 1 .5.
00:30
Which we have a calculator command for, which is normal cdf.
00:36
Negative 10 to the 10th is what i normally use for a large number.
00:41
And 1 .5 is our upper.
00:44
Then our mean is zero and our standard deviation is one.
00:49
And that becomes 0 .9332.
00:56
Then part b asks us for the probability, that z plus center equal to one, which is again similar to the last one, the area between negative infinity and one, which equals normal cdf, negative 10 to the 10th is our lower, 1 is our upper bound, 0 is our mean and 1 is our sigma.
01:31
And that is 0 .843.
01:36
Then part c, we have probability that z is between 1 and 1 .5, which is the area between 1 and 1 .5, which is the area between 1 and 1 .5...