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2 years ago

Noah saw some worms in his garden. He measured the length of each worm.

Mathematics

1 answer:

sergeinik [125]2 years ago

5 0

Answer:

9 worms are longer than 3 inches

Step-by-step explanation:

you can just count how many are in in the rows after 3 and that is your answer

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USA Today reports that about 25% of all prison parolees become repeat offenders. Alice is a social worker whose job is to counse

pychu [463]

Answer:

a) $P(X=0)=(4C0)(0.75)^0 (1-0.75)^{4-0}=0.0039$

$P(X=1)=(4C1)(0.75)^1 (1-0.75)^{4-1}=0.0469$

$P(X=2)=(4C2)(0.75)^2 (1-0.75)^{4-2}=0.211$

$P(X=3)=(4C3)(0.75)^2 (1-0.75)^{4-3}=0.422$

$P(X=4)=(4C4)(0.75)^2 (1-0.75)^{4-4}=0.316$

b) $E(X) = np = 4*0.75=3$

c) $Sd(X) =\sqrt{np(1-p)}=\sqrt{4*0.75*(1-0.75)}=0.866$

d) $P(X \geq 3) \geq 0.98$

And the dsitribution that satisfy this is $X\sim Binom(n=9,p=0.75$

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=4, p=1-0.25=0.75)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

Part a

$P(X=0)=(4C0)(0.75)^0 (1-0.75)^{4-0}=0.0039$

$P(X=1)=(4C1)(0.75)^1 (1-0.75)^{4-1}=0.0469$

$P(X=2)=(4C2)(0.75)^2 (1-0.75)^{4-2}=0.211$

$P(X=3)=(4C3)(0.75)^2 (1-0.75)^{4-3}=0.422$

$P(X=4)=(4C4)(0.75)^2 (1-0.75)^{4-4}=0.316$

Part b

The expected value is givn by:

$E(X) = np = 4*0.75=3$

Part c

For the standard deviation we have this:

$Sd(X) =\sqrt{np(1-p)}=\sqrt{4*0.75*(1-0.75)}=0.866$

Part d

For this case the sample size needs to be higher or equal to 9. Since we need a value such that:

$P(X \geq 3) \geq 0.98$

And the dsitribution that satisfy this is $X\sim Binom(n=9,p=0.75$

We can verify this using the following code:

"=1-BINOM.DIST(3,9,0.75,TRUE)" and we got 0.99 and the condition is satisfied.

4 0

2 years ago

Which statement describes if there is an extraneous solution to the equation √x-3 = x-5? A. there are no solutions to the equati

Brrunno [24]

Remember that an extraneous solution of an equation, is the solution that emerges from solving the equation but is not a valid solution.

Lets solve our equation to find out what is the extraneous solution:
 $\sqrt{x-3} =x-5$
$(\sqrt{x-3})^2 =(x-5)^2$
$x-3=x^2-10x+25$
$x^2-11x+28=0$
$(x-4)(x-7)=0$
$x-4=0$ and $x-7=0$
$x=4$ and $x=7$

So, the solutions of our equation are $x=4$ and $x=7$ . Lets replace each solution in our original equation to check if they are valid solutions:
- For $x=7$
$\sqrt{x-3} =x-5$
$\sqrt{7-3} =7-5$
$\sqrt{4} =2$
$2=2$
We can conclude that 7 is a valid solution of the equation.

- For $x=4$
$\sqrt{x-3} =x-5$
$\sqrt{4-3} =4-5$
$\sqrt{1} =1$
$1 \neq 1$
We can conclude that 4 is not a valid solution of the equation; therefore, 4 is a extraneous solution.

We can conclude that the correct answer is: D. the extraneous solution is x = 4

7 0

2 years ago

(7-4) + 17 / -14 + 2 x 5

Yuliya22 [10]

Answer:

165/14

Step-by-step explanation:

(7-4) + 17 / -14 + 2 x 5

3 + 17/-14 + 2 x 5

3 - 17/14 + 2 x 5

3 - 17/14 + 10

165/14

8 0

2 years ago

Given: The coordinates of rhombus WXYZ are W(0, 4b), X(2a, 0), YO, -4b), and Z(-2a, 0).

Shkiper50 [21]

Answer:

∴ MNOP is Rectangle

midpoint of XY (N) : (a , - 2b)

Step-by-step explanation:

W (0 , 4b) X ( 2a , 0) Y (0 , -4b) Z (-2a , 0)

M (midpoint of WX) : ( (0 + 2a)/2 , (4b + 0)/2) i. e. (a , 2b)

N (midpoint of XY) : ( (2a + 0)/2 , (0 - 4b)/2) i. e. (a , - 2b)

O (midpoint of YZ) : ( (0 - 2a)/2 , (- 4b + 0)/2) i. e. (- a , - 2b)

P (midpoint of ZW) : ( (0 - 2a)/2 , (4b + 0)/2) i. e. (- a , 2b)

MN: length = 2b + 2b = 4b MN segment perpendicular to x axis (slope undefined)

NO: length = a + a = 2a NO segment parallel to x axis (slope = 0)

OP: length = 2b + 2b = 4b OP segment perpendicular to x axis (slope undefined)

PM: length = a + a = 2a NO segment parallel to x axis (slope = 0)

MN = OP and MN // OP and MN ⊥ PM

NO = PM and NO // PM and NO ⊥ OP

∴ MNOP is Rectangle

midpoint of XY (N) : (a , - 2b)

please draw graph to prove

8 0

2 years ago

Y < 3 includes three as a possible solution

irakobra [83]

False...it does not include 3....it includes only numbers less then 3.

For it to include 3, u would need an equal sign in there..
Y < = 3...(thats less then or equal)...this would include 3

6 0

2 years ago