Traffic engineers install 12 street lights with new bulbs. the probability that a bulb will fail within 50000 hours of operation
is 0.26. assume that each of the bulbs fails independently. (a) what is the probability that fewer than two of the original bulbs will fail within 50000 hours of operation? (b) what is the probability that no bulbs will have to be replaced within 50000 hours of operation? (c) what is the probability that more than four of the original bulbs will need replacing within 50000 hours?
1 answer:
(a) The probability that 0 or 1 bulbs will fail is given by a suitable probabiity calculator as 0.14065.
(b) The probability that 0 bulbs will fail is given by a suitable probability calculator as 0.02696.
This is the probability that all bulbs will remain good: (1 - 0.26)^12.
(c) The probability that 5 or more bulbs will fail is the complement of the probability that 4 or fewer will fail. A suitable probability calculator shows the desired probability to be 0.17897.
(b) The probability that 0 bulbs will fail is given by a suitable probability calculator as 0.02696.
This is the probability that all bulbs will remain good: (1 - 0.26)^12.
(c) The probability that 5 or more bulbs will fail is the complement of the probability that 4 or fewer will fail. A suitable probability calculator shows the desired probability to be 0.17897.
You might be interested in
The measure of <u>angle b</u> is 112° and the measure of <u>angle c</u> is 68°
<h3>Calculating the measures of angles </h3>From the question, we are to determine the measures of the missing angles
From the diagram,
b = 112° (<em>Vertically opposite angles</em>)
∴ b = 112°
Also,
112° + c = 180° (<em>Sum of angles on a straight line</em>)
c = 180°- 122°
∴ c = 68°
Hence, the measure of <u>angle b</u> is 112° and the measure of <u>angle c</u> is 68°
Learn more on Calculating the measures of angles here: brainly.com/question/12274210
#SPJ1
