A major tire manufacturer wishes to estimate the mean tread life in miles for one of its tires. It wishes to develop a confidenc
2 answers:
Answer:
The required sample size is n=8,660.
Step-by-step explanation:
We have to calculate the minimum sample size that will give us a maximum margin of error of 500 miles, with a 90% confidence.
A pilot sample of n=50 give a sample standard deviation of 4,000 miles.
With the pilot sample we can calculate the population standard deviation as:
The equation for the margin of error is:
The z-value for a 90% confidence interval is z=1.645.
Then, we can estimate the sample size as:
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The linear equation in slope intercept form for population of Jose's town is y = 320x + 2400.
<u>Solution:</u>
Given, the population of Jose's town in 1995 was 2400 and the population in 2000 was 4000,
Let x represent the number of years since 1995.
We have to write a linear equation, in slope- intercept form, that represents this data.
Now, let the change in population per year be p.
Then, population in a year = population change per year number of years + population in 1995.
⇒population in a year = p x + population in 1995
⇒ population in a year = p x + 2400
Here we have an case that, population in 2000 is 4000
Then, number of years since 1995 = 5
So, 4000 = p 5 + 2400 ⇒ 5p = 4000 – 2400 ⇒ 5p = 1600 ⇒ p = 320
Then, our equation will be population in a year = 320x + 2400
Considering the population in a year as y ⇒ y = 320x + 2400.
Hence, the linear equation in slope intercept form is y = 320x + 2400.
Answer:
Step-by-step explanation:
If a function has a positive slope, that means the y value is increasing with respect to x. As you go down the x-axis, the y value will continuously increase.
First you want to plot the two sets of coords that they gave you, or else you wont know what the line looks like. Or, you could visually do it in your head. We're going down -4 on the x-axis and down 1 on the y-axis. Then for our second coords, we are going to 0 on the x-axis, then up 3 on the y-axis.
You could plot this for yourself, but im going to do it in my head for simplicity. We also need to find the slope of this function in order for us to find the y-intercept. The slope is change in y divided by the change in x. Subtract the initial position from the final position.
3 - 1 = 2
0 - (-4) = 4
2/4 = 1/2
The new equation is:
Everything is shaded below and to the right of the line. They said the line was solid, so that means less than or equal to,