The answer to the question
Answer:
15
Step-by-step explanation:
To solve this, divide 192 by 8:
192/9 = 24
Subtract 9 from 24:
24 - 9 = 15
Therefore, 8 times the sum of 9 and 15 is 192
All the triangles are similar, so the ratio of (long leg)/(short leg) is the same. The long leg of ΔADB is
.. AD = AC -DC = 20 -4
.. AD = 16
Then
.. (long leg)/(short leg) = AD/DB = BD/DC
.. 16/h = h/4
.. h^2 = 64
.. h = 8
Selection D is appropriate.
_____
You may see this again. The altitude (h) from the right angle in a right triangle is the geometric mean of segments AD and DC. That is,
.. h = √((AD)*(DC))
Answer:
5/4
Step-by-step explanation:
10/8 = 5/4
15/12 = 5/4
25/20 = 5/4
They all simplify to 5/4.
Hope this helps!
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.
