What is the probability of randomly selecting a z-score less than z = –0.80 from a normal distribution?
a)-0.2119
b)0.7881
c)0.2119
d)-0.7881
To find the probability of randomly selecting a z-score less than z = -0.80 from a normal distribution, you can use a standard normal distribution table or a calculator.
Step 1: Convert the z-score -0.80 to a cumulative probability.
The z-score represents the number of standard deviations a particular value is from the mean in a standard normal distribution. Using the standard normal distribution table or a calculator, you can find the cumulative probability associated with a specific z-score.
Step 2: Look up the cumulative probability in the standard normal distribution table.
For a z-score of -0.80, you would look up the corresponding cumulative probability in the standard normal distribution table. The table will provide the probability of selecting a z-score less than -0.80 (since it is a continuous distribution, we look for "less than" probabilities).
Step 3: Interpret the result.
Based on the lookup table or calculator, you should find that the cumulative probability for a z-score of -0.80 is approximately 0.2119.
Therefore, the correct answer is c) 0.2119.