Suppose that 50 identical batteries are being tested. after 8 hours of continuous use, assume that a given battery is still operating with a probability of 0.70 and has failed with a probability of 0.30. what is the probability that greater than 30 batteries will last at least 8 hours

0.9152

Step-by-step explanation:

Given that 50 identical batteries are being tested after  8 hours of continuous use.

Assumption is p = Probability for any bulb operating after 8 hours -=070

q= 0.30

n = number of trials = 50

X -- the no of bulbs which last more than 8 hours is binomial because

i) Each bulb is independent of the other

ii) There are only two outcomes, yes or no

Required probability = P(X>30)

=P(X=31)+P(X=31)++P(X=50)

=0.9159

=0.9152

Hence anwer is 0.9152

the answer is 8

step-by-step explanation:

3.14 x 8x8