Using the hypergeometric distribution, it is found that there is a 0.7568 = 75.68% probability that neither can wiggle his or her ears.
The people are chosen from the sample without replacement, which is why the <u>hypergeometric distribution</u> is used to solve this question.
Hypergeometric distribution:
The parameters are:
- x is the number of successes.
- N is the size of the population.
- n is the size of the sample.
- k is the total number of desired outcomes.
In this problem:
- 1000 people means that
- 130 can wiggle their ears, thus
- Two are selected, thus
.
The probability that neither can wiggle his or her ears is P(X = 0), thus:
0.7568 = 75.68% probability that neither can wiggle his or her ears.
A similar problem is given at brainly.com/question/24826394
You first find its intercepts: the x intercept is (5/3,0) and the y intercept is (0,5) (just plot those points). Then make the line connecting those 2 points!
The tangent line to a curve is the one that coincides with the curve at a point and with the same derivative, that is, the same degree of variation.
We have then:
y = 5x-x²
Deriving:
y '= 5-2x
In point (1, 4)
The slope is:
y (1) '= 5-2 * (1)
y (1) '= 3
The equation of the line will be:
y-f (a) = f '(a) (x-a)
We have then:
y-4 = 3 (x-1)
Rewriting:
y = 3x-3 + 4
y = 3x + 1
Answer:
the tangent line to the parabola at the point (1, 4) is
y = 3x + 1
the slope m is
m = 3
Let cos x = a, then
2a^2 + a - 1 = 0,
solving the quadratic equation, we have:
a = 0.5 or -1.
i.e. cos x = 0.5 or cos x = -1
for cos x = 0.5,
x = pi/3, 2pi - pi/3 = pi/3, 5pi/3
for cos x = -1,
x = pi
therefore, x = pi, pi/3, 5pi/3
Answer: B
