Step-by-step explanation:
girl=16
boy=18
picking a girl at random
the answer is = 1/16
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.
Margin of error formula:
ME = z * (Sigma) / √ n
z = 1.96 for a 95 % confidence interval;
Sigma = 3 ( the population standard deviation )
n = 500
ME = 1.96 * 3 / √500 =
= 1.96 * 3 / 22.36 =
= 5.88 / 22.36 = 0.263
Answer:
The margin error for a 95% confidence interval is 0.263.
