Statistic problem

[Guest]

What is the area under the standard normal curve between z = -1.28 and z = 1.28? (4dp)

What is the z-value that gives the left hand tail area equal to 0.0102? (2dp)

What is the absolute value of z such that the total area under the standard normal curve between –z and +z will be 0.7924? (2dp)

[Guest]

You understand, don't you, that you don't calculate* that, you look it up! There is probably a table in your textbook but there is also one here: https://www.math.arizona.edu/~rsims/ma4 ... ltable.pdf.
Look up the value for z= -1.28 and subtract that from the value for z= 1.28.

You can also calculate the values here: https://www.stattrek.com/online-calculator/normal.aspx.