
Chapter 7
PB
Continuous Probability Distributions
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Let us take another example, in terms of nding the probability of P(–2.00 ≤ z ≤ 2.00).
We know that the normal probability curve is symmetric and we have already calculated the
probability of P(0.00 ≤ z ≤ 2.00) = 0.4772. Since the curve is symmetric in nature, the probability
of P(–2.00 ≤ z ≤ 0.00) will also be 0.4772. Hence, the probability of P(–2.00 ≤ z ≤ 2.00) will be
P(–2.00 ≤ z ≤ 0.00) + P(0.00 ≤ z ≤ 2.00) = 0.4772 + 0.4772 = 0.9544
Figure 7.15 is a graphical representation of the probability P(–2.00 ≤ z ≤ 2.00). In a similar
manner, we can calculate the probability of z value between ...