Answer:C (-2, 1)
Step-by-step explanation:
Answer:
1. The population of interest is all city goverments in the U.S.
5. The parameter of interest is the proportion of the city goverments in the U.S. that provide electricity to their residents.
Step-by-step explanation:
Hello!
Missing questions:
Which of the following is true? Select all that apply.
- The population of interest is all city governments in the U.S.
- The population of interest is the 192 cities.
- The population of interest is all city governments that provide utilities to their residents.
- The population of interest is 6.25%
- The parameter of interest is the proportion of the city governments in the U.S. that provide electricity to their residents.
- The parameter of interest is 6.25%
- The population of interest is the 20 counties.
- The parameter of interest is the list of all counties in the U.S.
The objective of this essay is to test utilities provided by city governments, for this a sample of 20 counties was taken then contacted each city of them counting how many of them provided utilities to their residents, finding out that 12 out of 192 cities (6.25%) provided electricity to their residents.
The study variable is:
X: Number of city governments that provide utilities (electricity) to their residents, in a sample of 192.
The population of the study is the city governments in the U.S.
And the parameter of interest is the population proportion of city governments in the U.S. that provide electricity to their residents.
I hope it helps!
<u>Question 8</u>
a^2 + 7a + 12
= (a+3)(a+4)
When factorising a quadratic, the product of the two factors should equal the constant term (12), and the sum of the two factors should equal the linear term (7). To find the two factors, list out the factors of 12 (1x12, 2x6, 3x4) and identify the pair that adds up to 7 (3+4).
An alternative method if you get stuck during your exam would be to solve it algebraically using the quadratic formula and then write it in the factorised form.
a = (-7 +or- sqrt(7^2 - 4(1)(12)) / 2(1)
= (-7 +or- sqrt(1))/2
= -3 or -4
These factors are the negative of the values that would go in the brackets when written in factorised form, as when a = -3 the factor (a+3) would equal 0. (If it were positive 3 instead, then in the factorised form it would be a-3).
<u>Question 10</u>
-3(x - y)/9 + (4x - 7y)/2 - (x + y)/18
Rewrite each fraction with a common denominator so you can combine the fractions into one.
= -6(x - y)/18 + 9(4x - 7y)/18 - (x + y)/18
= (-6(x - y) + 9(4x - 7y) - (x + y)) /18
Expand the brackets and collect like terms.
= (-6x + 6y + 36x - 63y - x - y)/18
= (29x - 58y)/18
= 29/18 x - 29/9 y
Answer:
Step-by-step explanation:
2a-7+15-5a
2a-5a-7+15
-3a+8
Answer:
10
Step-by-step explanation:
Mean = 8+12+10+6+14 = 50
50 divided by 5 = 10
(Divided by 5 because there are 5 numbers)