Evaluate a + b for a = 12 and b = 6.

Answer:

13

Step-by-step explanation:

(3 - 2i)(3 + 2i)

Expand

(9 + 6i - 6i - 4i^2)

Add

(9 - 4i^2)

Convert i^2

i^2 = ([tex]\sqrt{-1}[/tex])^2 = -1

(9 - 4(-1))

Add

(9 + 4)

= 13

Answer:

13.

Step-by-step explanation:

(3 - 2i)(3 + 2i)

= (3 * 3) + (-2i * 3) + (2i * 3) + (-2i * 2i)

= 9 - 6i + 6i - 4[tex]\sqrt{-1} ^{2}[/tex]

= 9 - 4(-1)

= 9 + 4

= 13

Hope this helps!

Answer:

Step-by-step explanation:

Given that:

mean μ = 70

sample size = 25

sample mean = 73

standard deviation = 7

level of significance = 0.10

The null hypothesis and the alternative hypothesis can be computed as follows:

[tex]\mathtt{H_o : \mu = 70} \\ \\ \mathtt{H_1 : \mu > 70 }[/tex]

The z score for this statistics can be calculated by using the formula:

[tex]z = \dfrac{X- \mu}{\dfrac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \dfrac{73- 70}{\dfrac{7}{\sqrt{25}}}[/tex]

[tex]z = \dfrac{3}{\dfrac{7}{5}}[/tex]

[tex]z = \dfrac{3 \times 5}{{7}{}}[/tex]

z = 2.143

At level of significance of 0.10

degree of freedom = n -1

degree of freedom = 25 - 1

degree of freedom = 24

The p - value from the z score at   level of significance of 0.10 and degree of freedom of 24 is:

P - value = 1 - (Z < 2.143)

P - value =  1 - 0.9839

P - value =  0.0161

Decision Rule: since P value is lesser than the level of significance, we reject the null hypothesis.

Conclusion: We conclude that energy drink consumption increases heart rate.

Answer:

Step-by-step explanation:

In order to find B we must first angle C

To find angle C we use the sine rule

That's

[tex] \frac{ |a| }{ \sin(A) } = \frac{ |c| }{ \sin(C) } [/tex]

From the question

a = 15

A = 70°

c = 14

So we have

[tex] \frac{15}{ \sin(70) } = \frac{14}{ \sin(C) } [/tex]

[tex] \sin(C) = \frac{14 \sin(7 0 ) }{15} [/tex]

[tex]C = \sin^{ - 1} ( \frac{14 \sin(70) }{15} ) [/tex]

C = 61.288

Since we've found C we can use it to find B.

Angles in a triangle add up to 180°

To find B add A and C and subtract it from 180°

That's

A + B + C = 180

B = 180 - A - C

B = 180 - 70 - 61.3

To find b we can use the sine rule

That's

[tex] \frac{ |a| }{ \sin(A) } = \frac{ |a| }{ \sin(B) } [/tex]

[tex] \frac{15}{ \sin(70) } = \frac{ |b| }{ \sin(48.7) } [/tex]

[tex] |b| = \frac{15 \sin(48.7) }{ \sin(70) } [/tex]

b = 11.9921

Hope this helps you

Answer:

z(s) is in the acceptance region. We accept H₀  we did not find a significantly difference in the performance of the two machines therefore we suggest not to buy a new machine

Step-by-step explanation:

We must evaluate the differences of the means of the two machines, to do so, we will assume a CI  of 95%, and as the interest is to find out if the new machine has better performance ( machine has a bigger efficiency or the new machine produces more units per unit of time than the old one) the test will be a one tail-test (to the left).

New machine

Sample mean                  x₁ =    25

Sample variance               s₁  = 27

Sample size                       n₁  = 45

Old machine

Sample mean                    x₂ =  23  

Sample variance               s₂  = 7,56

Sample size                       n₂  = 36

Test Hypothesis:

Null hypothesis                         H₀             x₂  -  x₁  = d = 0

Alternative hypothesis             Hₐ            x₂  -  x₁  <  0

CI = 90 %  ⇒  α =  10 %     α = 0,1      z(c) = - 1,28

To calculate z(s)

z(s)  =  ( x₂  -  x₁ ) / √s₁² / n₁  +  s₂² / n₂

s₁  = 27     ⇒    s₁²  =  729

n₁  = 45    ⇒   s₁² / n₁    = 16,2

s₂  = 7,56   ⇒    s₂²  = 57,15

n₂  = 36     ⇒    s₂² / n₂  =  1,5876

√s₁² / n₁  +  s₂² / n₂  =  √ 16,2  + 1.5876    = 4,2175

z(s) = (23 - 25 )/4,2175

z(s)  =  - 0,4742

Comparing z(s) and  z(c)

|z(s)| < | z(c)|  

z(s) is in the acceptance region. We accept H₀  we did not find a significantly difference in the performance of the two machines therefore we suggest not to buy a new machine

The very hight dispersion of values s₁ = 27 is evidence of frecuent values quite far from the mean

Answer:

0.033316

Step-by-step explanation:

We use the z score formula to solve for this question.

Since we are given the number of samples in the question, our z score formula is given as:

z = (x-μ)/ S.E

where x is the raw score

μ is the sample mean

S.E is the Standard error.

x is the raw score = 900

μ is the sample mean = Population mean = 947

Standard error =

This is calculated as Population standard deviation/ √No of samples

= 205/√64.

= 205/8

= 25.625

We proceed to calculate the z score

z = (x-μ)/ S.E

z = 900 - 947/25.625

= -1.83415

Using the z score table for normal distribution,

P(x≤ z) = P(z ≤ -1.83) = P(x ≤ 900)

P(x<900) = 0.033316

Therefore, the probability the mean of the sample is below 900 is 0.033316

Answer:

The  equation is  [tex]r = \frac{4 }{ 1 + cos (\theta )}[/tex]

Step-by-step explanation:

From the equation we are told that

    The  Eccentricity: e = 1

    The  Directrix is   y = 4

Generally the polar equation for e =  1  and  y  =  + c is mathematically represented as

         [tex]r = \frac{e * c }{ 1 + ecos (\theta )}[/tex]

So

         [tex]r = \frac{1 * 4 }{ 1 + 1 * cos (\theta )}[/tex]

        [tex]r = \frac{4 }{ 1 + cos (\theta )}[/tex]

Answer:

No. By definition, mutually exclusive events cannot occur together.

Step-by-step explanation:

If two events are mutually exclusive, can they not occur concurrently because by definition, mutually exclusive events cannot occur together or at the same time. This ultimately implies that the events or outcome of the sampling is disjointed.

Mathematically, if two events A and B are mutually exclusive;

[tex]P(AnB) = 0[/tex]

From the above expression, we can deduce that the probability of the two (2) events occurring or having an intersection is zero (0).

[tex]P(A or B) = P(A) + P(B)[/tex]

From the above expression, we can deduce that the probability of either of the two (2) events occuring is the sum of the probability of each occurrence.

For example, when a fair die is tossed once, the outcomes are mutually exclusive.

P(d) = 1, 2, 3, 4, 5 and 6.

Other examples include;

1. Tossing a coin once, you'll either get a head or a tail but not a head and a tail at the same time.

2. In cards, both a king and an ace or a king and a queen are mutually exclusive because you can't have both occurring at the same time.

Answer:

Mean: 169.4

Median: 171

Mode: 181

Step-by-step explanation:

I first sorted the numbers by value, least to greatest.

145 147 153 153 167 170 170 172 181 181 181 182 185 185

We can see that 181 occurs the most, 3 times, so it's the mode.

The median of this set will be the middle number(s).

When we take away 6 numbers from both sides we are left with 170 and 172, and the mean of these two numbers is 171. So the median is 171.

We can add all the numbers and divide by 14 to get the mean.

[tex]147+153+170+172+185+181+182+185+181+170+181+167+153+145=2372\\\\2372\div14\approx169.4[/tex]

Hope this helped!

Answer:

8 home games and 10 away games

Step-by-step explanation:

Total home goals

= 8+5+9+8

= 30

Number of home games

= 30/3.75

= 8

Total away game goals

= 7+8+4+5

= 24

Number of away games

= 24/2.4

= 10

Answer:

i think it is 8 home and 10 away matches

Step-by-step explanation:

Question: Perform the following computation with radicals. Simplify the answer.  √6 • √8

Answer:

[tex] 4\sqrt{3} [/tex]

Step-by-step explanation:

Given, √6 • √8, to perform the computation, we would simply evaluate the radicals and try as much as possible to leave the answer in the simplest form in radicals.

Thus,

[tex] \sqrt{6}*\sqrt{8} = \sqrt{6*8} [/tex]

[tex] = \sqrt{48} [/tex]

[tex] = \sqrt{16*3} = \sqrt{16}*\sqrt{3}[/tex]

[tex] = 4\sqrt{3} [/tex]

Answer:

So option B is the answer.

If x + 2 is the only factor of the polynomial P(x) then we need to find the P(2) is Not Zero. Therefore, the option B is the correct answer.

Suppose the considered polynomial is of only one variable.

Then, the standard form of that polynomial is the one in which all the terms with higher exponents are written on left side to those which have lower exponents.

Given information;

If x + 2 is the only factor of the polynomial P(x) then we need to find the P(2) :

P(x) = x + 2

p(2) = 2 + 2

p(2) = 4

The P(2) is Not Zero.

Therefore, the option B is the correct answer.

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Answer:

11811 feet

Step-by-step explanation:

Hope it helps!

There are about 11,812 feet in 3.6 kilometers.

To convert kilometers to feet, we need to use the conversion factor:

1 kilometer = 3,280.84 feet.

Now, to find how many feet are in 3.6 kilometers,

we can multiply 3.6 by the conversion factor:

So, 3.6 kilometers x 3,280.84 feet/kilometer

= 11,811.504 feet.

Thus, Rounded to a whole number, there are about 11,812 feet in 3.6 kilometers.

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Answer:

y - 3 = -1/2(x - 1)

Step-by-step explanation:

Hey there!

Well point slope form is,

[tex]y - y_{1} = m(x - x_{1})[/tex]

We can use the point (1,3)

y - 3 = m(x - 1)

Now we need to find slope with the following formula,

[tex]\frac{y^2-y^1}{x^2-x^1}[/tex], we’ll use the points (1,3) and (5,1).

[tex]\frac{1-3}{5-1}[/tex]

-2/4

Slope or m = -1/2

y - 3 = -1/2(x - 1)

Hope this helps :)

Answer:

Step-by-step explanation:

1. The sum of one-third of a number and 27

= [tex]\frac{1}{3}\times x +27\\= 1/3x +27[/tex]

2. The product of a number squared and 4

[tex]Let\:the\:unknown\: number\: be \:x\\\\x^2\times4\\\\= 4x^2[/tex]

3.Write a verbal expression for 5n^3 +9.

The sum of the product and of 5 and a cubed number and 9

Answer:

≈ 3.6

Step-by-step explanation:

Calculate the distance d using the distance formula

d = [tex]\sqrt{(x_{2}-x_{1})^2+(y_{2}-y_{1})^2 }[/tex]

with (x₁, y₁ ) = (P(5, 1) and (x₂, y₂ ) = Q(3, 4)

d = [tex]\sqrt{(3-5)^2+(4-1)^2}[/tex]

   = [tex]\sqrt{(-2)^2+3^2}[/tex]

   = [tex]\sqrt{4+9}[/tex]

    = [tex]\sqrt{13}[/tex] ≈ 3.6 ( to the nearest tenth )

Answer:

3.6

Step-by-step explanation:

Look above bru

Answer:

Step-by-step explanation:

Two events A and B are said to be independent if the occurrence of one of the events does not affect the other occurring. For example, the event of tossing two coins is an independent event since they occur simultaneously. Two events are therefore independent if the following are true.

P(A|B) = P(A)

P(B|A) = P(B)

P(A and B) = P(A)P(B)

If A and B are independent events with P( A) = 0.35 and P( B) = 0.55,

then P( A| B) is a probability of A occurring provided that B has occurred. This is known as conditional probability for an independent event.

From the condition above for independent events, P(A|B) = P(A) and since P(A) =  0.35, hence P(A|B) =0.35

Answer:

[tex]1(x {}^{8} + x {}^{4} + 1)[/tex]

Step-by-step explanation:

[tex]x {}^{8} + {x}^{4} + 1 =1( x {}^{8} + x {}^{2} + 1)[/tex]

Hope this helps ;) ❤❤❤

Let me know if there is an error in my answer.

Answer:

The formula for the probability distribution is:

P(X = n) = q^(n - 1)p

= [0.2^(n - 1)]0.8

Step-by-step explanation:

This is a geometric probability distribution.

The probability of success p = 80% = 0.8

The probability of failure is q = 1 - p = 0.2

The formula is:

P(X = n) = q^(n - 1)p

= [0.2^(n - 1)]0.8

Here are a few ways 5% could be written in words:

-five percent

-five thousandths (0.05)

Hope this helps! :)

Answer:

0.05

Step-by-step explanation:

Assuming you mean as a decimal...

5/100 = 0.05

ALTERNATIVELY

5% = Five Percent

0.05 = Five Thousandths, Zero Point Zero Five

Answer:

option a

Step-by-step explanation:

give person above brainliest :)

Answer:

It rotated 180 degrees

Step-by-step explanation:

If you use this image and paste in on to google docs you will be able to rotate the image. Use this tool so that your can identify the amount of degrees.

If the Quadrilateral A'B'C'D' is the image of quadrilateral ABCD under a rotation about the origin, (0,0) then the angle of rotation is option (c) 180 degrees

In geometry a quadrilateral is a four-sided polygon, having four edges and four corners

The angle of rotation is a measurement of the amount, of namely angle, that a figure is rotated about a fixed point, often the center of a circle.

Given,

Quadrilateral A'B'C'D' is the image of quadrilateral ABCD under a rotation about the origin, (0,0)

Consider the coordinates of D and D'

D(2,3) and D'(-2,-3)

Connect D and D'

∠D0D' = 180 Degrees

Hence, If the Quadrilateral A'B'C'D' is the image of quadrilateral ABCD under a rotation about the origin, (0,0) then the angle of rotation is option (c) 180 degrees

Learn more about Quadrilateral and Angle of rotation here

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Answer:

48 soldiers

Step-by-step explanation:

60 soldiers                    20 days

x soldiers                       100 days

60 x 20 = 1200 = 100x

Therefore x = 1200/100 = 12

60 - 12 = 48

Hope that helped!!! k

Answer:

30 Soldiers

Step-by-step explanation:

Given:

1) No of soldiers=60

No of days=20

2) No of days=100

No of soldiers=?

No of soldiers to leave=?

Solution:

Let us use the cross multiplication method.

Let x be the no of soldiers.

No of days                                     No of  soldiers

1) 20                                                     60

2) 100                                                    x

by cross multiplying,

20x=100 x 60

20x=600

x=600/20

x=30 soldiers

Therefore, No of soldiers to leave =60-30=30 soldiers

Answer:

4

Step-by-step explanation:

i distributed the -2 to what's in the parentheses. that equal 0. I then moved the 4 to the zero so that it becomes positive. I just assumed that you were ask for Y

Step-by-step explanation:

y-4=-2(x+3)....eq(1)

y- 4= -2x-6

y=-2x-2...eq(2)

subtituting equation 2 in equation 1

(-2x-2)-4=-2x-6

-2x-6=-2x-6

=0

Correct question is ;

The grade appeal process at a university requires that a jury be structured by selecting eight individuals randomly from a pool of nine students and eleven faculty.​ (a) What is the probability of selecting a jury of all​ students? (b) What is the probability of selecting a jury of all​ faculty? (c) What is the probability of selecting a jury of six students and two ​faculty?

Answer:

A) 7.144 × 10^(-5)

B) 0.00131

C) 0.0367

Step-by-step explanation:

We are given;

Number of students = 9

Number of faculty members = 11

A) Now, the number of ways we can select eight students from 9 =

C(9, 8) = 9!/(8! × 1!) = 9

Also, number of ways of selecting 8 individuals out of the total of 20 = C(20,8) = 20!/(8! × 12!) = 125970

Thus, probability of selecting a jury of all​ students = 9/125970 = 7.144 × 10^(-5)

B) P(selecting a jury of all faculty) = (number of ways to choose 8 faculty out of 11 faculty)/(Total number of ways to choose 8 individuals out of 20 individuals) = [C(11,8)]/[C(20,8)] = (11!/(8! × 3!))/125970 = 0.00131

C) P(selecting a jury of six students and two faculty) = ((number of ways to choose 6 students out of 9 students) × (number of ways to choose 2 faculty out of 11 faculty))/(Total number of ways to choose 8 individuals out of 20 individuals) = [(C(9,6) × C(11,2)]/125970

This gives;

(84 × 55)/125970 = 0.0367

Answer:

7/10 mi

Step-by-step explanation:

The total distance is 3 miles = 30/10 miles.

The other distances added gives 7/10+7/10+9/10 = 23/10

Therefore the last hop from Kingwood to Silvergrove is 30/10 - 23/10 = 7/10

Answer:

18.90

Hope i got it right

Answer:

B

Step-by-step explanation:

Option A:

1.50÷18≈0.0833

3.00÷36≈0.0833

4.50÷54≈0.0833

Option B:

0.75÷15=0.05

Option C:

2.20÷15=0.146

Answer:

the answer is a=b

Step-by-step explanation:

Rewrite 3 3/4 as an improper fraction

3 3/4 = 15/4

Now you have

15/5 / 5/7

When you divide fractions, change the division to multiplication and flip the second fraction over:

15/4 x 7/5

Now multiply the top numbers together and the bottom numbers together:

( 15 x 7) / (4 x 5) = 105/20

Write as a proper fraction:

105/20 = 5 1/4