So we are given that the mean is 42% and the sd (standard deviation) is 8%
Assuming our data is normal we can use the 68-95-99 rule
So one thing you should realize is that 42% + 8% is 50% which is passing. That is one standard deviation higher. So we use:
100 - 68 - 13.5 - 2.35 - 0.15 = 16. That means 16% of students passed the test. Which is terrible. They probably need to hit the books more.
Anyways if you have any question feel free to message me!
Hopes this helps!
Equation of a line is given by y - y1 = m(x - x1) where m is the slope and (x1, y1) is any point on the line.
y - (-2) = 4(x - 3)
y + 2 = 4x - 12
y = 4x - 12 - 2
y = 4x - 14
1/3 rise=1 run=2. Therefore the answer is 1/3
Answer:
d)
because that would be the same as 
2.3, 2.6, 2 4/5
2 4/5= 2.8