The life of light bulbs is distributed normally. The standard deviation of the lifetime is 20 hours and the mean lifetime of a bulb is 500 hours. Find the probability of a bulb lasting for between 480 and 526 hours.

The probability of a bulb lasting for between 480 and 526 hours=0.74454

Step-by-step explanation:

We are given that

Standard deviation of the lifetime,hours

Mean, hours

We have to find the probability of a bulb lasting for between 480 and 526 hours.

Hence, the probability of a bulb lasting for between 480 and 526 hours=0.74454

1/4 and 8/3 because:

the reciprocal if 4 is 1/4 because 4 is used as 4/1 and the opposite of that is 1/4. the opposite of 3/8 is 8/3 so that is the answer.

.19875994384

step-by-step explanation:

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