Answer:
We need an SRS of scores of at least 153.
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 
.
So it is z with a pvalue of 
, so 
Now, find M as such
In which 
is the standard deviation of the population and n is the size of the sample.
How large an SRS of scores must you choose?
This is at least n, in which n is found when 
. So
Rounding to the next whole number, 153
We need an SRS of scores of at least 153.
Answer:
6.5 bottles
Step-by-step explanation:
convert liters to ml 1 bottle= 1000ml
divide how much she drank by 1000ml
6500÷1000=6.5
Answer:
45%
Step-by-step explanation:
Simply divide your partial amount (18 in this case) by your total (40), and you then multiply your answer from 18/40= .45 by 100, and you get 45. This is 45%
Answer:
1/24
Step-by-step explanation:
We can't subtract two fractions with different denominators. So you need to get a common denominator. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.
So we multiply 11 by 8, and get 88.Then we multiply 7 by 12, and get 84.
Next we give both terms new denominators -- 12 × 8 = 96.
So now our fractions look like this:
88
/96
-84
/96
Step 2
Since our denominators match, we can subtract the numerators.
88 − 84 = 4
So the answer is:
4
/96
Step 3
Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?
To find out, we try dividing it by 2...
Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:
4
/96
÷ 2 =2
/48
Let's try dividing by 2 again...
Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:
2
/48
÷ 2 =1
/24
Let's try dividing by 2 again...
No good. 2 is larger than 1. So we're done reducing. There you have it! The final answer is:
11
/12
-7
/8=1
/24
