Answer:
z-test.
Step-by-step explanation:
We want to perform an hypothesis test for a population mean.
In the case that the <u>standard deviation of the population is known</u> and the population distribution is normal, even if the sample is small, <u>we will use a z-test</u>.
The usual case is to not know the standard deviation of the population, in which case a t-test is adequate instead of a z-test, taking into account the degrees of freedom of the sample.
Answer:
b
Step-by-step explanation:
it bbbbbbbbbbbbbbb yeah b or d
2r-3r+10=20
Move all terms to the left:
2r-3r+10-(20)=0
add all the numbers together, and all the variables
-1r-10=0
move all terms containing r to the left, all other terms to the right
-r=10
r=10/-1
r=-10
Answer:
(x + 6)(x + 13)
Step-by-step explanation:
Given
x² + 19x + 78
Consider the factors of the constant term (+ 78) whuch sum to give the coefficient of the x- term (+ 19)
The factors are + 6 and + 13 , since
6 ×13 = + 78 and 6 + 13 = + 19 , then
x² + 19x + 78 = (x + 6)(x + 13) ← in factored form
You look at the hundreths place (4) and if it is 5 or more you round the tenths place up. so the number is rounded to 9.2
