Using the normal distribution, it is found that there is a 0.877 = 87.7% probability of a bulb lasting for at most 569 hours.
<h3>What is Normal Probability Distribution?</h3>The z-score of a measure X of a normally distributed variable with mean and standard deviation is given by:
- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
The mean and the standard deviation are given, respectively, by:
= 530
= 625
25
The probability of a bulb lasting for at most 569 hours is the p-value of Z when X = 569, hence:
z = = 1.36
Z = 1.36 has a p-value of 0.9131
0.9131 x 100 = 91.31 % probability of a bulb lasting for at most 569 hours.
More can be learned about the normal distribution at brainly.com/question/24663213
#SPJ1