Answer:
The probability that an 18-year-old man selected at random is greater than 65 inches tall is 0.8413.
Step-by-step explanation:
We are given that the heights of 18-year-old men are approximately normally distributed with mean 68 inches and a standard deviation of 3 inches.
Let X = <u><em>heights of 18-year-old men.</em></u>
So, X ~ Normal()
The z-score probability distribution for the normal distribution is given by;
Z = ~ N(0,1)
where, = mean height = 68 inches
= standard deviation = 3 inches
Now, the probability that an 18-year-old man selected at random is greater than 65 inches tall is given by = P(X > 65 inches)
P(X > 65 inches) = P( >
) = P(Z > -1) = P(Z < 1)
= <u>0.8413</u>
The above probability is calculated by looking at the value of x = 1 in the z table which has an area of 0.8413.
You can take x = a, 2y = b and then can apply the binomial theorem.
The expansion of given expression is given by:
Option D: is
It provides algebraic expansion of exponentiated(integer) binomial.
According to binomial theorem,
Taking a = x, and b =2y, we have n = 7, thus:
Thus, Option D: is correct.
Learn more about binomial theorem here:
Answer:
Step-by-step explanation:
the mean is given by:
In our case this is:
side note: the main difference between sample mean and population mean is in the 'context'. However, the method to calculate them is the same.
By context I mean: if this the items are taken from some larger category for example: the ages of a few 'students' from a 'class'. Here 'students' are the sample from a larger set that is 'class'. The mean of the 'few students' will be called sample mean. In contrast, if we take the mean of the ages of the whole class then this is called population mean. (population mean == mean of the whole set)
In our case we aren't told exactly where these numbers come from, is this the whole set or a sample from it, the lack of context allows us to assume that the mean can either be population mean or sample mean. So we can safely use any symbol or
.