1.Find P(Z<-1.97 or Z>2.5),P(-2.08<Z<2.08) and P(0<Z<1.73)

Question

2.The masses of packages from a particular machine are normally distributed with mean 200g and standard deviation 2g. Find the probability that a randomly selected package from the production line of the machine weighs i.less than 197g.

Answer 1

This webpage is a must if you are studying this topic and your up-to-date textbook
no longer has normal distribution tables in the back

http://davidmlane.com/normal.html

for the first one, find P(z < -1.97) and P(z > 2.5), then add them up
for the 2nd and 3rd, use the "between" button

Answer 2

Can you explain the second one?

Answer 3

The web site shows you how to use the area to the right of a point. Now do to the left of a point.