Answer:
n=1849
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The population proportion have the following distribution
Solution to the problem
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by 
and 
. And the critical value would be given by:
The margin of error for the proportion interval is given by this formula:
(a)
And on this case we have that 
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
Assuming that the proportion is estimated 
. And replacing into equation (b) the values from part a we got:
And rounded up we have that n=1849
Answer: 18m
Step-by-step explanation:
9m + 9
Simplify:
9+9=18
Hence, the answer to 9m + 9 is 18m.
The true statements about the triangles RST and DEF are: (a), (d) and (e)
<h3>How to determine the true statements?</h3>
The statement ΔRST ≅ ΔDEF means that the triangles RST and DEF are congruent.
This above implies that:
- The triangles can be mapped onto each other by rigid transformations such as reflection, translation and rotation
- The transformation does not include dilation
- Corresponding sides are congruent
The above means that the possible true statements are: (a), (d) and (e)
Read more about transformation at:
brainly.com/question/4289712
#SPJ1
Answer:
$22.34
Step-by-step explanation:
24 pennies is .24 of a dollar
62 nickels will be: (62 x 5) / 100 = 3.10
55 dimes is 5.5
16 quarters will be 4.0
19 fifty-cents will be 9.5
Add them up to get $22.34 if I’m right.
Hope this helped.
Answer:
See photo
Step-by-step explanation:
We can fill out many of these pretty easily. Look at the picture below. (Black numbers represent what information they already gave us)
Now, for the actual math.
If a total of 46 seventh-graders were surveyed and 28 seventh-graders spent more than an hour on their phone, then that means that there would have to be 46-28=18 students that spend less than an hour on their phone.
If there are 43 total students that spend more than an hour on their phone, and 28 of those are seventh-graders, then there are 43-28=15 eighth-graders that spend more than an hour on their phone
Then, if there are 27 total eighth-graders, and 15 of those spend more than an hour, then that leaves 27-15=12 eighth-graders that spend less than an hour on their phone.
Lastly, figure out the total numbers.
There are 18 seventh-graders and 12 eighth-graders that spend less than an hour on their phone, so there is a total of 18+12 = 30 students that spend less than an hour on their phone.
There are a total of 46 seventh-graders and 27 eighth-graders that were surveyed, which is a total of 73 students surveyed.
