Historical data for a local steel manufacturing company shows that the average number of defects per standard sheet of steel is 2. In addition, the number of defects per unit is distributed according to Poisson distribution.
A batch has just been completed. What is the probability that the first three units manufactured in this batch will contain at least a total of 4 defects?
A.8488
B.7149
C.1512
D.2851

A.8488

Step-by-step explanation:

Poisson distribution formula :

, where = mean of the distribution.

Let x be the random variable that represents the number of defects.

Given : The average number of defects per standard sheet of steel is 2.

For 3 sheets , the  average number of defects per standard sheet of steel = 2 x 3 = 6

i.e.

Now , the probability that the first three units manufactured in this batch will contain at least a total of 4 defects will be :-

Hence, the probability that the first three units manufactured in this batch will contain at least a total of 4 defects will be 0.8488.

Thus , the correct option is A .8488.

45

step-by-step explanation:

to find a percentage, add a decimal in front and multiply it by the other number.

.25 times 180= 45