Answer:
The z-score for SAT exam of junior is much small than his ACT score. This means he performed well in his ACT exam and performed poor in his SAT exam.
Step-by-step explanation:
Mean SAT scores = 1026
Standard Deviation = 209
Mean ACT score = 20.8
Standard Deviation = 4.8
We are given SAT and ACT scores of a student and we have to compare them. We cannot compare them directly so we have to Normalize them i.e. convert them into such a form that we can compare the numbers in a meaningful manner. The best way out is to convert both the values into their equivalent z-scores and then do the comparison. Comparison of equivalent z-scores will tell us which score is higher and which is lower.
The formula to calculate the z-score is:
Here, μ is the mean and σ is the standard deviation. x is the value we want to convert to z score.
z-score for junior scoring 860 in SAT exam will be:
z-score for junior scoring 16 in ACT exam will be:
The z-score for SAT exam of junior is much small than his ACT score. This means he performed well in his ACT exam and performed poor in his SAT exam.
X + y = 1.5
x = 1.5 - y
Bring that into 5x + 60y = 35
5 (1.5 - y) + 60y = 35
7.5 - 5y + 60y = 35
62.5y = 35
y = 0.56
Bring that into x + y = 1.5
x + 0.56 = 1.5
x = 1.5-0.56
x = 0.94
Hope this helps.
- Max
Answer:
The lines for each pair of equations are perpendicular, because the slopes for both of these have negative reciprocals.
Step-by-step explanation:
-5x+10y=5
x-2y=-1
2y=x-(-1)
2y=x+1
y=1/2x+1/2