Answer:
Choice B.
Step-by-step explanation:
Given the reported values:
x f(x)
-3 -2
-2 0
-1 2
0 2
1 0
2 -8
3 -10
4 -20
We must locate the interval where f(x) is greater than zero.
The table shows f(x) is negative for x values less than -2 and greater than 1.
Between x = -2 and x = 1, f(x) takes positive values. Thus, the interval where f(x) is positive is (-2, 1).
Hence, the correct choice is B.
Let X represent the numbered marbles.
P(21≤ X ≤27) = 0.4332
P( 0 ≤ z ≤ 6/σx) = 0.4332; for this case, Z stands for the z-score
1.5 = 6/σx
solving for σx gives us 4
<span>5.7 liters of a 5% solution combined with 4.3 liters of a 40% solution.
To begin, define the problem with formulas.
x Represents the liters of the 5% solution utilized.
10-x Represents the liters of the 40% solution used.
This forms an equation: 5% of x plus 40% of (10-x) equals 20% of 10.
0.05x + 0.40(10-x) = 0.20 * 10
Now, distribute the 0.40 coefficient.
0.05x + 4.0 - 0.40x = 0.20 * 10
Next, combine the terms.
4.0 - 0.35x = 2.0
Add 0.35x to each side.
4.0 = 2.0 + 0.35x
Subtract 2 from both sides.
2.0 = 0.35x
Lastly, divide both sides by 0.35.
5.7 = x
Thus, 5.7 liters of a 5% solution is required. To determine the volume of the 40% solution, subtract from 10.
10.0 - 5.7 = 4.3</span>
