9514 1404 393
Answer:
A
Step-by-step explanation:
The axis of symmetry of quadratic ax²+bx+c is x=-b/(2a). For the given equation, the axis of symmetry is ...
x = -4/(2(3/2)) = -4/3
The only graph with its vertex at x=-4/3 is graph A.
_____
<em>Additional comment</em>
You can also make the correct choice by evaluating the equation at a couple of different values of x. Convenient ones are x= -1, or 0, or +1. The value at x=0 is the y-intercept, (0, -2), which seems to be a point on all of the graphs. The value at x=1 is 3/2+4-2 = 3.5, which looks like it is only seen on graph A.
To solve this, we use the z test.
The formula:
z = (x – u) / s
where x is sample value = 20, u is the mean = 15, and s is
the standard deviation = 2.5
z = (20 – 15) / 2.5
z = 2
Since we are looking for values greater than 20, this is
right tailed test. We use the standard distribution tables to find for P.
P = 0.0228
Therefore:
number of students = 100 * 0.0228 = 2.28
<span>2 to 3 students will get greater than 20 measurement</span>
Answer:
100
Step-by-step explanation:
For a box and whispers plot, each section represents 25% of the data. Therefore, the area from 85-99 represents 25% of the data.
25% of 24 students= 6 students
Final answer: 6 students
Answer:3360
Step-by-step explanation:
