Question

The probability that a certain type of transistor will last more than 2,000 hours of use is 0.6. If 100 transistors are selected at random what is the probability that:

a. Does not less than 60 nor more than 70 last more than 2,000 hours?

b. Does at least 50 last more than 2,000 hours?

Answer 1

a);

b)

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