For a Standard Normal Distribution 1. P(z is less than or equal to 1.33) 2. P(z is less than or equal to -2.33) 3. P(z is greater than or equal to 2.35) 4. P(-2.33 is less than z is less than 2.33) 5. P(2.33 is less than z is less than 2.95)
Standard normal distribution tables such as: http://www.math.unb.ca/~knight/utility/NormTble.htm give probabilities for 0<Z<infinity. For these ranges, you can read directly, for example, P(Z<1.96)=0.975. So for #1, you read directly on the line 1.3 and column 0.03. For #2, we note that the distribution is symmetrical about Z=0, so P(Z<-2.33) is the same as P(Z>2.33) which again is the same as 1-P(Z<2.33) because we know that the area under a probability distribution function adds up to 1. For the remaining questions, work is similar to #2.
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