Answer:
(B) The correct interpretation of this interval is that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points.
Step-by-step explanation:
Confidence interval is the range the true values fall in under a given <em>confidence level</em>.
Confidence level states the probability that a random chosen sample performs the surveyed characteristic in the range of confidence interval. Thus,
90% confidence interval means that there is 90% probability that the statistic (in this case SAT score improvement) of a member of the population falls in the confidence interval.
Answer:
a) 35, b) 25, c) 60
Step-by-step explanation:
The number of girls is 10 more than the number of boys, so it's a good thing to choose a variable to represent the number of boys.
Number of boys: b
Number of girls: b + 10
Ratio of girls:boys is 7:5, so
"Cross multiply" to get
There are 25 boys. There are 10 more girls, so the number of girls is 35, and the total number of students is 60.
That's a packed classroom!
Answer:
13/18
Step-by-step explanation:
26/2= 13
36/2= 18
13/18
