Answer: 0.0475
Step-by-step explanation:
Let x = random variable that represents the number of a particular type of bacteria in samples of 1 milliliter (ml) of drinking water, such that X is normally distributed.
Given:
The probability that a given 1-ml will contain more than 100 bacteria will be:
∴The probability that a given 1-ml will contain more than 100 bacteria
0.0475.
The expression in company B represents that is is in arithmetic progression where first term is 42000 and common difference is 1800 . So we have to use the formula of sum of n terms which is
Where a is the first term, n is the nth term, d is the common difference
On substituting there values,we will get
= 15(84000+52200) = 15*136200 =2043000
And for company A, it is
Difference between them =2043000-2002500= 40500
So the correct option is the second option .