Answer:

Step-by-step explanation:

Hope this helps.
Answer:
negative
positive
Step-by-step explanation:
Answer:
you answer is b
Step-by-step explanation:
ik bc i did it last year
.._+_+
Answer:
a) 22497.7 < μ< 24502.3
b) With 99% confidence the possible error will not exceed 1002.3
Step-by-step explanation:
Given that:
Mean (μ) = 23500 kilometers per year
Standard deviation (σ) = 3900 kilometers
Confidence level (c) = 99% = 0.99
number of samples (n) = 100
a) α = 1 - c = 1 - 0.99 = 0.01

Using normal distribution table,
is the z value of 1 - 0.005 = 0.995 of the area to the right which is 2.57.
The margin of error (e) is given as:

The 99% confidence interval = (μ - e, μ + e) = (23500 - 1002.3, 23500 + 1002.3) = (22497.7, 24502.3)
Confidence interval = 22497.7 < μ< 24502.3
b) With 99% confidence the possible error will not exceed 1002.3
Answer:
y = 60
Step-by-step explanation:
<h3>Step 1: Make sense of the given</h3>
"The ratio of y to x is 3"
This means that, 
"The sum of y and x is 80"
This means, 
<h3>Step 2: Make use of the facts</h3>
If
, then
.
We can plug this into the other equation by substitution:

This simplifies to:

Which we can solve out and get:
.
<h3>Step 3: Plug and Chug</h3>
We solved for x, but we need the value of y.
So, we go back to the equation we first derived: "
".
And now we substitute the value of x, into this.

By solving this out, we get:

So, the value of y is 60.