Answer:the answer is 66.98
Step-by-step explanation:
Answer:
0.8413 = 84.13% probability of a bulb lasting for at most 605 hours.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
The standard deviation of the lifetime is 15 hours and the mean lifetime of a bulb is 590 hours.
This means that 
Find the probability of a bulb lasting for at most 605 hours.
This is the pvalue of Z when X = 605. So



has a pvalue of 0.8413
0.8413 = 84.13% probability of a bulb lasting for at most 605 hours.
54.039 in words are fifty-four and thirty-nine thousandths
Answer:
it might be 48.9 but im not sure
Step-by-step explanation:
Answer:
C which is 12
36 and 48 are both a multiple of 12