Question

Let the random variable X follow a normal distribution with a mean of 80 and a variance of 100.

1. Find the probability that X is less than 55

2. Find the probability that X is greater than 72

3. Find the probability that X is between 75 and 90

Answer 1

The probability that a random variable X following a normal distribution with mean 80 and variance 100 is less than 55, greater than 72, or between 75 and 90 can be found using Z-scores and standard normal tables.

Step-by-step explanation:

To find the probability that X is less than 55, is greater than 72, or is between 75 and 90 when X is normally distributed with a mean of 80 and a variance of 100, we use the properties of the normal distribution and standard normal distribution tables.

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