A) 3(a - b) = 3*a +3*-b = 3a - 3b EQUAL
b) 2a(2 + b) = 4a + 2ab NOT EQUAL
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:
the slope is -2
Step-by-step explanation:
C - Parenthesis first (3-1)=2, then distribute the 4. 4x2=8, next add 5, 8+5=13.
Answer:
I rlly don't know.
Step-by-step explanation:
Ask ur math teacher for help.
I hope this helps u out!