Answer: 42
Step-by-step explanation:
if the bookstore has 64 copies,
yesterday it was sold 1/4 , so it was sold 64/4=16
today it was sold 1/8 from what remained, which is 6(see below)
64-16=48
48/8=6
the store has left 48-6=42
a. The standard error is equal to the standard deviation divided by the square root of the sample size:
SE = (23 ppm)/√18 ≈ 5.42 ppm
b. The t statistic is given by the difference between the true and sample means, divided by the standard error:
t = (192 ppm - 180 ppm)/SE ≈ 2.21
c. The p-value is approximately 0.0204.
d. Since p < 0.05, the difference is significantly different, so we reject the null hypothesis.
e. A type I error might have occurred, since it's possible that the null hypothesis was true, but we ended up rejecting it.
<h3>
There are 3 answers: Choice A, Choice D, Choice F</h3>
Explanation:
2 & 1/2 = 2.5
10 + (-2.5) can be represented by starting with 10 and then dropping by 2.5, which is what choice A is saying
or we can start with -2.5 and add on 10. This works because we can add numbers in any order, example: 2+3 = 3+2 = 5. So starting with -2.5 and adding on 10 is represented by choice D's and choice F's examples
8 x (5 x 2 + 3)=104 because 5 x 2 is 10, 10 + 3 is 13, and 13 x 8 is 104.
