Hello Marcella,
Let Z be the a standard normal random variable. That is, Z has a normal distribution with mean 0 and standard deviation 1. To find c such that P(Z>c) = 0.3002, you need to find a value of Z( a point on the Z-axis) such that the area under the normal curve to the right of Z = c is 0.3002. You can use a table or some technology (a computer program like Excel or a graphing calculator) to find the appropriate value of c. Most typical normal distribution tables are cumulative distribution tables. That is, they give the total area to the left of any value of Z. If the area to the right of c is 0.3002, then the area to the left of c is 1 - 0.3002 = .6998. Now use a table to find the value of c such that P(Z≤c) =.6998,
and you will find that
c ≅ .52
Hope that helps.
William
