This hard anyone help?

An example problem in a Statistics textbook asked to find the probability of dying when making a skydiving jump.

MArishka [77]

Answer:

(a) 0.999664

(b) 15052

Step-by-step explanation:

From the given data of recent years, there were about 3,000,000 skydiving jumps and 21 of them resulted in deaths.

So, the probability of death is $\frac{21}{3000000}==0.000007$ .

Assuming, this probability holds true for each skydiving and does not change in the present time.

So, as every skydiving is an independent event having a fixed probability of dying and there are only two possibilities, the diver will either die or survive, so, all skydiving can be regarded as is Bernoulli's trial.

Denoting the probability of dying in a single jump by $q$ .

$q=7\times 10^{-6}=0.000007$ .

So, the probability of survive, $p=1-q$

$\Rightarrow p=1-7\times 10^{-6}=0.999993.$

(a) The total number of jump he made, n=48

Using Bernoulli's equation, the probability of surviving in exactly 48 jumps (r=48) out of 48 jumps (n=48) is

$=\binom(n,r)p^rq^{n-r}$

$=\binom(48,48)(0.999993)^{48}(0.000007)^{48-48}$

$=(0.999993)^{48}=0.999664$ (approx)

So, the probability of survive in 48 skydiving is 0.999664,

(b) The given probability of surviving =90%=0.9

Let, total $n$ skydiving jumps required to meet the surviving probability of 0.9.

So, By using Bernoulli's equation,

$0.9=\binom {n }{r} p^rq^{n-r}$

Here, r=n.

$\Rightarrow 0.9=\binom{n}{n}p^nq^{n-n}$

$\Rightarrow 0.9=p^n$

$\Rightarrow 0.9=(0.999993)^n$

$\Rightarrow \ln(0.9)=n\ln(0.999993)$ [ taking $\log_e$ both sides]

$\Rightarrow n=\frac {\ln(0.9)}{\ln(0.999993)}$

$\Rightarrow n=15051.45$

The number of diving cant be a fractional value, so bound it to the upper integral value.

Hence, the total number of skydiving required to meet the 90% probability of surviving is 15052.

3 0

3 years ago

Find the volume of a pyramid with a square base, where the perimeter of the base is

Kobotan [32]

Answer:

6.8 cubic feet

Step-by-step explanation:

7.3/4=1.825, which is the side length, 1.825*1.825=20.2575 and then ypu divide 20.2575 by 3 because it is a pyramid and that gives you 6.7525

4 0

3 years ago

Assign a variable to each quantity and write each statement as an inequality. Then give an example

RideAnS [48]

Answer:

1.

Variable: x

Inequality: x ≤ 12

Value that matches: 12

2.

Variable: y

Inequality: y < 66

Value that matches: 60

Step-by-step explanation:

Solving (1):

Let x be the variable

Reading through the question, we have the inequality to be represented by "at most".

At most is used for less than or equal to.

Hence, the expression can be represented by:

x ≤ 12

The range of this inequality is limited to all natural number that do not exceed 12.

Examples are 8, 2, 11, 12

Solving (2):

Let the variable be y

Reading through the question, we have the inequality to be represented by "below".

Below means less than

Hence, the expression can be represented by:

y < 66

The range of this inequality is limited to all number less than 66.

Examples are 65, 1 , 60......

6 0

3 years ago

Which ordered pair is a solution of the equation?<br> -3x – y = 6<br> Choose 1 answer:

Aleks [24]

Answer:

Step-by-step explanation:

I can not see your answers to choose but with this equation for 2 variables, you can replace the values of x and y and see if that is right or not.

For example, to know (-2,5) is a solution, you replace x= -2 and y= 5

into this equation: -3x -y = 6

and you have: -3*(-2) -5 =6

or 6-5 =6, and you find that is impossible, so (-2.5) is not a solution.

Hope you understand it

5 0

3 years ago

Place on,number line

Alex

A goes between -1 and -1/2

8 0

3 years ago

Read 2 more answers