Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.28.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Answer:
horizontal.
Step-by-step explanation:
it goes straight up
Answer:=
Solution: -2<c<3
Interval Notation: (-2,3)
Step-by-step explanation:
-3<5c+7<22
-3<5c+7 : c>-2
5c+7<22 : c<3
combine the intervals
c>-2 and c<3
-2<c<3
Answer:
g(f(x)) = 6x - 14
General Formulas and Concepts:
<u>Pre-Algebra</u>
<u>Algebra I</u>
Step-by-step explanation:
<u>Step 1: Define</u>
g(x) = 3x + 1
f(x) = 2x - 5
<u>Step 2: Find</u>
- Substitute: g(f(x)) = 3(2x - 5) + 1
- Distribute 3: g(f(x)) = 6x - 15 + 1
- Combine like terms: g(f(x)) = 6x - 14