There are 12 months in a year so. 85x12=1020
Answer:
The sum is 17,690 nine
Step-by-step explanation:
100+4200 is 4,300
4,300+50 is 4,350 if you rounded that to the nearest 10,000 it's 10,000
Explain cause I think you're missing something from the question
Answer:
8y = -6
Step-by-step explanation:
Simply add the equations as you would numbers.
The 'x's cancel each other out. The 'y's add together as normal numbers.
9 + (-15) = -6
Hope that this helps!
Answer:
CI = 21 ± 0.365
Step-by-step explanation:
The confidence interval is:
CI = x ± SE * CV
where x is the sample mean, SE is the standard error, and CV is the critical value (either t score or z score).
Here, x = 21.
The standard error for a sample mean is:
SE = σ / √n
SE = 3.2 / √510
SE = 0.142
The critical value is looked up in a table or found with a calculator. But first, we must find the alpha level and the critical probability.
α = 1 - 0.99 = 0.01
p* = 1 - (α/2) = 1 - (0.01/2) = 0.995
Using a calculator or a z-score table:
P(x<z) = 0.995
z = 2.576
Therefore:
CI = 21 ± 0.142 × 2.576
CI = 21 ± 0.365
Round as needed.