A small school with 60 total students records how many of their students attend school on each of the 180 days in a school year. The mean number of students in attendance daily is 55 students and the standard deviation is 4 students. Suppose that we take random samples of 5 school days and calculate the mean number of students x ˉ in attendance on those days in each sample. Calculate the mean and standard deviation of the sampling distribution of x ˉ.

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.

answer: (-8,4) are the coordinates of a

step-by-step explanation:

let the side of square abcd is x .

thus the area of square abcd is .

now, by the diagram area of triangle ead= 1/2 × ea × ad = 1/2 × ea × x

( because ad is the side of square)

and, according to the question,

the areas of square abcd and right ead are equal.

⇒

⇒ea=2x

thus, ea: ab=2: 1

therefore, point a divides line segment eb into the ratio 2: 1.

⇒ by sectional formula coordinates of a are,

=

=

=(-8, 4)

thus the coordinates of a are (-8,4)