Answer:
Step-by-step explanation:
a). =
=
= [Since, i =
]
b). =
=
= 5 ± 2i [Since, i = ]
c). =
=
=
= [Since, i =
]
A set of data has a normal distribution with a mean of 5.1 and a standard deviation of 0.9. Find the percent of data between 4.2 and 5.1.
Answer: The correct option is B) about 34%
Proof:
We have to find
To find , we need to use z score formula:
When x = 4.2, we have:
When x = 5.1, we have:
Therefore, we have to find
Using the standard normal table, we have:
=
or 34.13%
= 34% approximately
Therefore, the percent of data between 4.2 and 5.1 is about 34%