Find the value of the variable x in the equation x - 21 = 8.
A) -13
B) 29
C) -29
D) 13​

Answer:

(a) The probability that X is at most 30 is 0.9726.

(b) The probability that X is less than 30 is 0.9554.

(c) The probability that X is between 15 and 25 (inclusive) is 0.7406.

Step-by-step explanation:

We are given that 11% of all steel shafts produced by a certain process are nonconforming but can be reworked. A random sample of 200 shafts is taken.

Let X = the number among these that are nonconforming and can be reworked

The above situation can be represented through binomial distribution such that X ~ Binom(n = 200, p = 0.11).

Here the probability of success is 11% that this much % of all steel shafts produced by a certain process are nonconforming but can be reworked.

Now, here to calculate the probability we will use normal approximation because the sample size if very large(i.e. greater than 30).

So, the new mean of X, [tex]\mu[/tex] = [tex]n \times p[/tex] = [tex]200 \times 0.11[/tex] = 22

and the new standard deviation of X, [tex]\sigma[/tex] = [tex]\sqrt{n \times p \times (1-p)}[/tex]

                                                                  = [tex]\sqrt{200 \times 0.11 \times (1-0.11)}[/tex]

                                                                  = 4.42

So, X ~ Normal([tex]\mu =22, \sigma^{2} = 4.42^{2}[/tex])

(a) The probability that X is at most 30 is given by = P(X < 30.5)  {using continuity correction}

        P(X < 30.5) = P( [tex]\frac{X-\mu}{\sigma}[/tex] < [tex]\frac{30.5-22}{4.42}[/tex] ) = P(Z < 1.92) = 0.9726

The above probability is calculated by looking at the value of x = 1.92 in the z table which has an area of 0.9726.

(b) The probability that X is less than 30 is given by = P(X [tex]\leq[/tex] 29.5)    {using continuity correction}

        P(X [tex]\leq[/tex] 29.5) = P( [tex]\frac{X-\mu}{\sigma}[/tex] [tex]\leq[/tex] [tex]\frac{29.5-22}{4.42}[/tex] ) = P(Z [tex]\leq[/tex] 1.70) = 0.9554

The above probability is calculated by looking at the value of x = 1.70 in the z table which has an area of 0.9554.

(c) The probability that X is between 15 and 25 (inclusive) is given by = P(15 [tex]\leq[/tex] X [tex]\leq[/tex] 25) = P(X < 25.5) - P(X [tex]\leq[/tex] 14.5)   {using continuity correction}

       P(X < 25.5) = P( [tex]\frac{X-\mu}{\sigma}[/tex] < [tex]\frac{25.5-22}{4.42}[/tex] ) = P(Z < 0.79) = 0.7852

       P(X [tex]\leq[/tex] 14.5) = P( [tex]\frac{X-\mu}{\sigma}[/tex] [tex]\leq[/tex] [tex]\frac{14.5-22}{4.42}[/tex] ) = P(Z [tex]\leq[/tex] -1.70) = 1 - P(Z < 1.70)

                                                          = 1 - 0.9554 = 0.0446

The above probability is calculated by looking at the value of x = 0.79 and x = 1.70 in the z table which has an area of 0.7852 and 0.9554.

Therefore, P(15 [tex]\leq[/tex] X [tex]\leq[/tex] 25) = 0.7852 - 0.0446 = 0.7406.

Answer:

Step-by-step explanation:

Q(x)=x² − 6x − 2

To find Q(−4) substitute the value of x which is - 4 into Q(x)

That's

Q(-4) = (-4)² - 6(-4) - 2

Q(-4) = 16 + 24 - 2

We have the final answer as

Hope this helps you

Answer:

150<60+30n

Step-by-step explanation:

150 is the maximum amount that she can spend on gas. (which is the total)

she already spend $60

each fill up (n) costs 30

Answer:

the answer is B)

Step-by-step explanation:

Answer:

The velocity is  [tex]v = 886.96 \ m/s[/tex]

Step-by-step explanation:

From the question we are told that

    The period of each revolution is  [tex]T = 1\ day = 24 \ hours[/tex]

    The angle  is [tex]\theta = 30^o[/tex]

     The radius is  [tex]r = 3387.5 \ miles[/tex]

Generally the linear speed is  mathematically represented as

        [tex]v = w * r[/tex]

Where  [tex]w[/tex] is the angular speed which is mathematically represented as

       [tex]w = \frac{2 \pi }{T}[/tex]

substituting values

       [tex]w = \frac{2 *3.142 }{24}[/tex]

        [tex]w = 0.2618 \ rad/s[/tex]

Thus  

         [tex]v = 0.261833 * 3387.5[/tex]

        [tex]v = 886.96 \ m/s[/tex]

Answer:

Step-by-step explanation:

∠a is alternate interior angle to ∠ECD

∠b is alternate interior angle to ∠BCD

so:

If AB || CD then:

m∠a = m∠ECD = 25° + 42° = 67°

m∠b = 42°

Answer:

1 bulb

Step-by-step explanation:

First find the number of blue bulbs

60 * 20 %

60 * .2

12 blue bulbs

10 % of the blue were damaged

12 * 10%

12 * .10

1.2

Rounding to the nearest whole number

1 bulb

Step-by-step explanation:

thats shape is a delta

:)

Answer:

arrow head

Step-by-step explanation:

Answer:

3179.25

Step-by-step explanation:

Hello!

To find the volume of a cylinder we use the equation

[tex]V = \pi r^{2} h[/tex]

V is volume

r is radius

h is height

Put in what we know. It is says to use pi as 3.14

[tex]V = 3.14 * 7.5^{2} *18[/tex]

Solve

V = 3.14 * 56.25 * 18

V = 3179.25

Hope this Helps!

Answer:

T-test

Step-by-step explanation:

Significance of correlation between two variables x and y measures the strength and direction of their relationship. This is used to make future forecasts of the behaviour of a variable under study.

Correlation coefficient can be used to measure significance of correlation, but we can also use the t-test.

T-test is a statistics that is inferential. It measures the significance of difference between the means of two groups.

T-test is the statistic of choice when carrying out hypothesis testing.

T distribution values and degrees of freedom are used to determine statistical significance.

For example the means of two samples can be compared to determine of the come from the same population

Explanation:

We have 4 options for the first choice and 3 options for the next. So there are 4*3 = 12 different combos possible. The tree diagram below shows 12 different paths to pick from. For instance, the right-most path has us pick the number 4 and the color yellow.

Answer:

3x18 = 3 (10+8) is an example of the commutative property of multiplication

Step-by-step explanation:

Answer: commutative property of multiplication

Step-by-step explanation:

Answer:

Step-by-step explanation:

One of the method of analysing the distribution of a dataset is by finding the mean of the dataset which is part of the measure of central of tendency.

Mean of a dataset is also known as the average and it is the ratio of the sum of the individual dataset to the sample size.

Mathematically xbar = ΣXi/N where

ΣXi is the sum of the individual dataset

N is the sample size

xbar is the mean

From the formula,  ΣXi = xbar * N

This means that the sum of the individual dataset (all values in the dataset) is equal to the product of the mean (xbar) and the sample size(N).

Hence the statement that In any sample data set, the sum of all the values is equal to the product of the mean and the sample size."is TRUE

Answer:

UAE is in the Gulf Standard Time zone.

It is GMT + 4

Breakfast: 7 am; GMT 3 am

School time 8 am: GMT 4 am

Lunch time: 12:30 pm; GMT 8:30 am

Step-by-step explanation:

UAE is in the Gulf Standard Time zone.

It is GMT + 4

Breakfast: 7 am; GMT 3 am

School time 8 am: GMT 4 am

Lunch time: 12:30 pm; GMT 8:30 am

Answer:

we could work this out by geometric sequence

Step-by-step explanation:

G1=2, G2=4, we have a formula,Gn=G1r^n-1

G2=G1 (r)^1, 4=2r, r=2

G30=G1 (2)^29=1,073,741,824 bacterium

Answer:

M= 521.1 g

Step-by-step explanation:

1st.  Find the volume of the cube:   V=3³=27 cm³

As the weight of V= 1 cm³ cube  is 19.3 g the weight of the cube=27 cm³ is

M=27*19.3= 521.1 g

Answer:

342 m

Step-by-step explanation:

SIn(20) * 1000 = RS

342 = RS

Answer:

[tex]\huge\boxed{f(n)=\left\{\begin{array}{ccc}f(1)=20\\f(n)=f(n-1)-4\end{array}\right}[/tex]

Step-by-step explanation:

[tex]f(n)=20-4(n-1)=20+(n-1)(-4)\\\\\text{It's an explicit formula of an arithmetic sequence:}\\\\f(n)=a_1+(n-1)(d)\\\\a_1-\text{first term}\\d-\text{common difference}\\\\\text{Conclusion:}\\\text{Next term}=\text{previous one}\ -4\\\\\text{The recursive formula:}\\\\\huge\boxed{f(n)=\left\{\begin{array}{ccc}f(1)=20\\f(n)=f(n-1)-4\end{array}\right}[/tex]

Answer:

Step-by-step explanation:

someone answered already

Answer:

2  c an of blue and 5 can of yellow

Step-by-step explanation:

Answer:

35 or 25

Step-by-step explanation:

Answer: Option "a" is the only expression that represents a function.

Step-by-step explanation:

A function f(x) = y is a "operator" that takes an input element, x, and assigns it to only one output element, y.

So, if we have that for a given value of x.

f(x) = y and f(x) = h

where y and h are different values, then this is not a function, because is assigning the input value x to two different output values.

Let's see the different options:

a) {(1, 2), (4, −2), (8, 3), (9, −3)}

This points are of the form (x, y)

We can see that each value of x is assigned to only one value of y, so this can represent a function.

b)  y^2 = 16 − x^2

Ok, suppose that x = 0, then:

y^2 = 16 - 0 = 16

then we have that y*y = 16.

So y can take two different values:

y = 4 ---> 4*4 = 16

y = -4 ---> -4*-4 = 16.

So this is not a function.

c) 2x^2 + y^2 = 5

First, we want to isolate y in one side:

y^2 = 5 - 2*x^2

Here we have a similar case to the option b, and we can use a similar argument to prove that this is not a function, so we can discard this.

d) x = 7.

Ok, this is not a relation between two variables, so this is not a function, as if x is the input value, we have only one value of x that solves the equation.

Answer:

a) f(6)=(6)^2+4(6)+1=65

b)f (x+9)=(x+9)^2+4 (x+9)+1=(x^2+18x+81)+(4x+36)+1=x^2+22x+117

f (-x)=(-x)^2-4x+1

Answer:

point A is the rays endpoint

Step-by-step explanation:

Answer:

The "endpoint" of a ray is the origin point of the ray, or the point at which the ray starts.

Step-by-step explanation:

A ray starts at a given point, the endpoint, and then goes in a certain direction forever ad infinitum.  The origin point of a ray is called "the endpoint".

Cheers.

Add up the P(x) values that correspond to x = 2 through x = 4

0.07+0.22+0.22

So we have a 51% chance of getting an x value such that 1 < x < 5

By using the probability distribution table, the value of P(1<x<5) is 0.51

Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true

A probability distribution is the mathematical function that gives the probabilities of occurrence of different possible outcomes for an experiment. It is a mathematical description of a random phenomenon in terms of its sample space and the probabilities of events

Given,

We have to find the value of P(1<x<5)

P(1<x<5) = P(2)+P(3)+P(4)

P(2)=0.07

P(3)=0.22

P(4)=0.22

P(1<x<5) = 0.07+0.22+0.22 =0.51

Hence, the value of P(1<x<4)= 0.51

Learn more about Probability and Probability distribution here

https://brainly.com/question/14210034

#SPJ2

Answer:

Step-by-step explanation:

Given the sequence of interest earned by Marius on his savings account as

200, 208, 216.30, 225, …, the sequence of interest forms a geometric sequence since they have a common ratio.

[tex]r =\frac{T_2}{T_1}= \frac{T_3}{T_2}= \frac{T_4}{T_3}\\ r =\frac{208}{200}= \frac{216.30}{208}= \frac{225}{216.30} \approx 1.04[/tex]

To get how much total interest will Marius have earned by the 30th year the account is active, we will find the sum of the first 30 terms of the geometric sequence as shown.

[tex]S_n =\frac{ a(r^n-1)}{r-1} \ for \ r> 1\\ \\\\ n = 30, a = 200, r = 1.04\\S_{30} = \dfrac{ 200(1.04^{30}-1)}{1.04-1}\\\\S_{30} = \dfrac{ 200(3.243-1)}{0.04}\\\\S_{30} = \dfrac{ 200(2.243)}{0.04}\\\\S_{30} = \dfrac{ 448.6}{0.04}]\\\\S_{30} = 11,215[/tex]

Hence total interest that Marius will earn by the 30th year the account is active is 11,215.

the correct answer is

S30= 200(1-1.04^n)/1-1.04

i took the test

You said    - 1/3 - 3/5 x  =  1/2

Multiply each side by 3 :

- 1 - 9/5 x  =  3/2

Multiply each side by 5 :

- 5 - 9x  =  15/2

Multiply each side by 2 :

- 10 - 18x = 15

Add 10 to each side :

- 18x  =  25

Divide each side by -18 :

x = - 25/18

or  x = - 1 and 7/18 (same thing)

Answer:

  C.  70°

Step-by-step explanation:

The inscribed angle marked 15° intercepts an arc that is double that measure, so the intercepted arc on the right is 2×15° = 30°.

The external angle marked 20° is half the difference of the intercepted arcs, so is ...

  20° = (1/2)(x - 30°)

  40° = x - 30° . . . . . . multiply by 2

  70° = x . . . . . . . . . . . add 30°

The value of x is 70°.

Step-by-step explanation:

Suppose, John walks with a speed x

Then, John can jog at a speed 2x

[tex]total \: time \: = \frac{total \: distance}{average \: speed} [/tex]

TOTAL TIME

[tex]0.9 = \frac{5}{2x} + \frac{2}{x} [/tex]

Further solving :

x = 5 mph

Average jogging speed (2x) = 10 mph

Answer:

10mph

Step-by-step explanation:

We know that John's total trip is 0.9 hours, so let's try to figure out how much of that time is spent jogging, and how much of it is spent walking.

We can do that by naming the time he takes to jog a mile y.

An equation would be:

5y+2(2y)=0.9

5y+4y=0.9

y=0.1

It takes him 0.1 hours, or 6 minutes to jog a mile.

Since he jogged 5 miles, his jogging time is 0.5 hours, or 30 minutes.

Now,

Let's name the speed he jogs x (miles per hour)

This allows us to set up another equation.

Note that:

Speed=distance/time

His jogging speed is x.

x=5/0.5

x=10

His average jogging speed is 10 miles an hour.

Answer:

x = 5

AC = 6

DC = 8

Step-by-step explanation:

∆ABC ~ ∆CDE

Therefore, [tex] \frac{AB}{ED} = \frac{AC}{DC} [/tex]

AB = 3

ED = 4

AC = x + 1

DC = x + 3

Plug in the values and solve for x:

[tex] \frac{3}{4} = \frac{x + 1}{x + 3} [/tex]

Cross multiply

[tex] 3(x + 3) = 4(x + 1) [/tex]

[tex] 3x + 9 = 4x + 4 [/tex]

[tex] 3x - 4x = -9 + 4 [/tex]

[tex] -x = -5 [/tex]

[tex] x = 5 [/tex]

Plug in the value of x and find AC and DC

AC = x + 1 = 5 + 1 = 6

DC = x + 3 = 5 + 3 = 8

36×7

=252

Explaination :

First Multiply 6 and 7 we get 42 !

Write 2 and 4 will be added to the product of 3×7

We get 21 and add 4 here

So we get 252

Answer:

[tex]36 \times 7 = 252[/tex]

Step-by-step explanation:

Firstly multiply 6 with 7 you have to write 2 and take 4 carry and then multiply 7 with 3 u get 21 now add the number u carry in 21 u get ur answer. 252.

Hope it helps u mate

Answer:

A) C = 1/96

B) P(x<=1, y<=1) = 1/128 or 0.0078125 to 7 places

C) P(x+y<=1) = 5/2305, or 0.0021701 to 7 places

Step-by-step explanation:

f(x,y) = C x (1+y)

A)

To find C, we need to integrate the volume under region bound by

0 <= x <= 4, and

0 <= y <= 4

This volume equals 1.0.

Find integral,

int( int(f(x,y),x=0,4), y = 0,4) = 96C

therefore C = 1/96

or

F(x,y) = x (1+y) / 96  ............................(1)

B)

P(x<=1, y<=1)

Repeat the integral, substitute the appropriate limits,

P = int( int(F(x,y),x=0,1), y = 0,1)

= 1/128 or 0.0078125

P(x<=1, y<=1) = 1/128 or 0.0078125 to 7 places

C)

P(x+y<=1)

From the function, we know that this is going to be less than one half of the probability in (B), closer to 1/4 of the previous.

It will be again a double integral, as follows:

P = int( int(F(x,y),x=0,1-y), y = 0,1)

= 5/2304

= 0.0021701 (to 7 decimals)

P(x+y<=1) = 5/2305, or 0.0021701 to 7 places