Question

Light bulbs from a production line are tested. Of the 150 bulbs tested, 7 were defective. What is the probability of a bulb not being defective? What if 60,356 bulbs are produced in a week?

a) 0.953
b) 0.965
c) 0.981
d) 0.989

Answer 1

The probability of a bulb not being defective is 0.953 or 95.3%, calculated by subtracting the probability of a defect (7/150) from 1. Assuming production consistency, this probability can be applied to estimate the number of non-defective bulbs in larger batches.

Step-by-step explanation:

To calculate the probability of a bulb not being defective from the batch tested, we can use the complement rule. There were 7 defective bulbs out of 150 tested. To find the probability of a bulb not being defective, we subtract the probability of a bulb being defective from 1.

The probability of a bulb being defective is 7/150. Therefore, the probability P of a bulb not being defective is P = 1 - (7/150). Calculating this gives P = 143/150, which can be approximated as 0.953 or 95.3%.

Now, if 60,356 bulbs are produced in a week, we would expect the proportion of non-defective bulbs to remain consistent with the sampled probability, although actual numbers may vary due to production inconsistencies or sampling errors. However, for estimation purposes, we would multiply 60,356 by the probability of a bulb being non-defective (0.953) to estimate the number of non-defective bulbs.