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3 years ago

Need help, please explain

Mathematics

1 answer:

Sever21 [200]3 years ago

7 0

Answer:

(x - 2)(x + 2)

Step-by-step explanation:

x² - 4 ← is a difference of squares and factors in general as

a² - b² = (a - b)(a + b), that is a product of two binomials

Given

x² - 4

= x² - 2²

= (x - 2)(x + 2)

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6.3.6. Among the early attempts to revisit the death postponement theory introduced in Case Study 6.3.2 was an examination of th

kakasveta [241]

Answer:

So the Null hypothesis is rejected in this case

Step-by-step explanation:

The number of celebrities is n = 348

So to solve this we would assume that p is the percentage of people that died on the month preceding their birth month

Generally if there is no death postponement then p will be mathematically evaluated as

$p = \frac{1}{12}$

This implies the probability of date in one month out of the 12 months

Now from the question we can deduce that the hypothesis we are going to be testing is

$Null Hypothesis \ \ H_0 : p = 0.083$

This is a hypothesis is stating that a celebrity dies in the month preceding their birth

$Alternative \ Hypothesis H_1 : p < 0.083$

This is a hypothesis is stating that a celebrity does not die in the month preceding their birth

is c is the represent probability for each celebrity which either c = 0 or c = 1

Where c = 0 is that the probability that the celebrity does not die on the month preceding his/ her birth month

and c = 1 is that the probability that the celebrity dies on the month preceding his/ her birth month

Then it implies that

for

n= 1 + 2 + 3 + .... + 348 celebrities

Then the sum of c for each celebrity would be $c_s = 16$

i.e The number of celebrities that died in the month preceding their birth month

We are told that the significance level is $\alpha = 0.05$ , the the z value of $\alpha$ is

$z_{\alpha } = 1.65$

This is obtained from the z-table

Since this test is carried out on the left side of the area under the normal curve then the critical value will be

$z_{\alpha } = - 1.65$

So what this implies is that $H_o$ will be rejected if

$z \le -1.65$

Here z is the test statistics

Now z is mathematically evaluated as follows

$z = \frac{c - np}{\sqrt{np_o(1- p_o)} }$

$z = \frac{16 - (348 *0.083)}{\sqrt{348*0.083 (1- 0.083)} }$

$z =-2.50$

From our calculation we see that the value of z is less than $-1.65$ so the Null hypothesis will be rejected

Hence this tell us that the evidence provided is not enough to conclude that 16 celebrities died a month to their birth month

8 0

3 years ago

Help please

algol [13]

An Ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.

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