Answer: (15.47, 24.53)
Step-by-step explanation:
We know that the confidence interval for population mean is given by :_

, where n= sample size.
= standard deviation.
= sample mean.
z*= Critical value.
Given : n= 450


Critical value for 95% confidence = z*=1.96 [From z-value table]
Then, the 95% confidence interval will be :-




Hence, the 95% confidence interval for the mean change in score μ μ in the population of all high school seniors. : (15.47, 24.53)
2x + 5y = -3 ⇒ 2x + 5y = -3
1x + 8y = 4 ⇒ <u>2x + 16y = 8
</u> -<u>11y</u> = <u>-11 </u>
-11 -11
y = 1
2x + 5(1) = -3
2x + 5 = -3
<u> -5 -5</u>
<u>2x</u> = <u>-8</u>
2 2
x = -4
(x, y) = (-4, 1)
2x + 1y = 7 ⇒ 2x + 1y = 7
1x - 2y = -14 ⇒ <u>2x - 4y = -28</u>
<u>5y</u> = <u>35</u>
5 5
y = 7
2x + 7 = 7
<u> -7 -7</u>
<u>2x</u> = <u>0</u>
2 2
x = 0
(x, y) = (0, 7)
Answer:
D would be the answer Nonth grades at peak school
All of them have the same answer of -8 except the last one.
Follow the order of operations. Evaluate absolute value first.
-3^2+8/2*4-9
Then evaluate exponents
9+8/2*4-9
Then evaluate multiplication and division from left to right
9+4*4-9
9+16-9
Then evaluate addition and subtraction from left to right
25-9
16
Final answer: 16