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.
78
step by step explanation:
first: divide 600 and 15
answer to 600/15: 40
second: divide 3120 and 40
final answer: 78
Discriminant = square root (b^2 -4*a*c)
square root (64 -4*1*12) =
square root (16) =
4
Therefore it has 2 rational soltions
It’s twelve because you multiple x by 12 and get y.