Tom and Carl start 200 miles apart, running towards each other. Tom runs 5 miles per hour faster than Carl. If they meet after 10 hours, how fast are they running?

Answer:

732 samples ;

752 samples

Step-by-step explanation:

Given :

α = 90% ; M.E = 0.03 ; p = 0.58 ; 1 - p = 1 - 0.58 = 0.42

Using the relation :

n = (Z² * p * (1 - p)) / M.E²

Zcritical at 90% = 1.645

n = (1.645² * 0.58 * 0.42) / 0.03²

n = 0.65918769 / 0.0009

n = 732.43076

n = 732 samples

B.)

If no prior estimate is given, then p = 0.5 ; 1 - p = 1 - 0.5 = 0.5

n = (Z² * p * (1 - p)) / M.E²

Zcritical at 90% = 1.645

n = (1.645² * 0.5 * 0.5) / 0.03²

n = 0.67650625 / 0.0009

n = 751.67361

n = 752 samples

Answer:

Hence the probability that she paid cash is  0.105

Step-by-step explanation:  

P(cash) = 0.3  

P(credit card ) = 0.3  

P(debit card ) = 0.4  

P ( more than $50 | cash ) = 0.2  

P (more than $50 | credit card ) =0.9  

P (more than $ 50 |debit card ) = 0.6  

P ( more than $50) = P ( more than $50 | cash )* P (cash) + P (more than $50 credit card ) * P(credit card ) + P (more than $ 50 |debit card )* P(debit card )  

= 0.2 * 0.3 + 0.9 * 0.3 + 0.6* 0.4  

= 0.57  

P ( more than $50) = P ( more than $50 | cash )* P (cash) / P ( more than $50)  

= 0.2* 0.3 / 0.57  

= 0.105

Answer:

hi

Step-by-step explanation:

Answer:

The answer is "0.1397".

Step-by-step explanation:

[tex]\mu=3511\\\\[/tex]

variance [tex]\ S^2= 253,009\\\\[/tex]

standard deviation [tex]\sigma =\sqrt{253,009}=503\\\\[/tex]

Finding the probability in which the weight will be less than [tex]4617 \ grams\\\\[/tex]

[tex]P(X<4617)=p[z<\frac{4617-3511}{503}]\\\\[/tex]  

                      [tex]=p[z<\frac{1106}{503}]\\\\=p[z< 2.198]\\\\= .013975\approx 0.1397[/tex]

Answer:

cos2x=-17/145

Step-by-step explanation:

Recall cos2x=cos^2x-sin^2x

Or cos2x=cos^2x-(1-cos^2x)*

Or cos2x=2cos^2x-1**

*By a Pythagorean Identity

**Combined like terms

I'm going to use third identity from above because I only have to find cosx or cos^2x to get requested answer for cos2x.

Recall Pythagorean identity 1+tan^2x=sec^2x.

Plug in our tangent valuem...

1+(9/8)^2=sec^2x

1+81/64=sec^2x

145/64=sec^2x

Cosine and secant are reciprocals of each other.

64/145=cos^2x

Now we are ready to plug in and get final answer:

cos2x=2cos^2x-1

cos2x=2(64/145)-1

cos2x=128/145-1

cos2x=-17/145

Step-by-step explanation:

here's the answer to your question

Answer:

A = 14 in²

Step-by-step explanation:

The area (A) of the triangle is calculated as

A = [tex]\frac{1}{2}[/tex] bh ( b is the base and h the perpendicular height )

Here b = 7 and h = 4 , then

A = [tex]\frac{1}{2}[/tex] × 7 × 4 = [tex]\frac{1}{2}[/tex] × 28 = 14 in²

Answer:

The bones were 12,485 years old at the time they were​ discovered.

Step-by-step explanation:

Amount of the element:

The amount of the element after t years is given by the following equation, considering the decay rate proportional to the amount present:

[tex]A(t) = A(0)e^{-kt}[/tex]

In which A(0) is the initial amount and k is the decay rate, as a decimal.

The radioactive element​ carbon-14 has a​ half-life of 5750 years.

This means that [tex]A(5750) = 0.5A(0)[/tex], and we use this to find k. So

[tex]A(t) = A(0)e^{-kt}[/tex]

[tex]0.5A(0) = A(0)e^{-5750k}[/tex]

[tex]e^{-5750k} = 0.5[/tex]

[tex]\ln{e^{-5750k}} = \ln{0.5}[/tex]

[tex]-5750k = \ln{0.5}[/tex]

[tex]k = -\frac{\ln{0.5}}{5750}[/tex]

[tex]k = 0.00012054733[/tex]

So

[tex]A(t) = A(0)e^{-0.00012054733t}[/tex]

A scientist determined that the bones from a mastodon had lost 77.8 ​% of their​ carbon-14. How old were the bones at the time they were​ discovered?

Had 100 - 77.8 = 22.2% remaining, so this is t for which:

[tex]A(t) = 0.222A(0)[/tex]

Then

[tex]0.222A(0) = A(0)e^{-0.00012054733t}[/tex]

[tex]e^{-0.00012054733t} = 0.222[/tex]

[tex]\ln{e^{-0.00012054733t}} = \ln{0.222}[/tex]

[tex]-0.00012054733t = \ln{0.222}[/tex]

[tex]t = -\frac{\ln{0.222}}{0.00012054733}[/tex]

[tex]t = 12485[/tex]

The bones were 12,485 years old at the time they were​ discovered.

Answer:

Step-by-step explanation:

The area to be resurfaced is the area of the

whole circle including garden and lanes minus  

the area of the garden.

Area of a circle is (pi)r2

radius of garden is (1/2)diameter = 8 m

Garden area:  (pi)82 = 64(pi) m2

Diameter of garden plus traffic lanes is

16 + 2(6) because we add 6 m to both sides

of the diameter of the garden.

Full diameter = 16+12 = 28 m

Full radius = 28/2 = 14 m

Full area:  (pi)142 = 196(pi) m2

Area to be resurfaced:

196(pi) - 64(pi) = 132(pi) m2  ≅ 415 m2

9514 1404 393

Answer:

  C.  h ≥ 1.9 in

Step-by-step explanation:

As the final step, divide both sides of the inequality by 5.3:

  (5.3h)/5.3 ≥ 10/5.3

  h ≥ 1.9

Answer:

B

Step-by-step explanation:

The square root function's graph is graph (b). This makes logical sense, because, when taking the square root (the principal root in particular), a general rule is that both the input and the output must be positive. Moreover, if one were to create a table of values to find points on the graph of the function, each of the points can be found on graph (b).

[tex]f(x)=\sqrt{x}[/tex]

x         y

1          1

4         2

9         3

16        4

Therefore graph (B) is the correct answer.

Answer:

7x^2 -35x +7

Step-by-step explanation:

7(x^2 – 5x + 1)

Distribute

7x^2 -7*5x +7*1

7x^2 -35x +7

Answer:

c= none of the above

Step-by-step explanation:

-3x- 6/10

This has two separate terms, a term with a variable

-3x  and a term with a constant -6/10

A=3/6x1/10  This has only one term

b=- 3/10x-6  This has a different x term -3/10  which is not -3

c= none of the above

Answer:

1320 ways

Step-by-step explanation:

Number of contestants = 12

Positions that are n be awarded = First, Second, Third

Number of contestants who could be first = 12 (all 12 contestants)

Number of contestants who could be second = 11 (all 12 contestants - first)

Number of contestants who could be third = 10 (all 12 contestants - first and second )

The number of ways prices can be given :

(1st * 2nd * 3rd) = 12 * 11 * 10 = 1320 ways

the value of Zis 8.

Z =2^3=8

Now we have to,

find the required value of Z.

→ Z = 2^3

→ [Z = 8]

Therefore, value of Z is 8.

9514 1404 393

Answer:

Step-by-step explanation:

If we let a, b, c represent tickets booked on airlines A, B, C, respectively, then we have ...

  a + b + c = 55

  a - b = 6

  -2b + c = 5

Using the last two equations to write expressions for a and c, we have ...

  a = b +6

  c = 5 +2b

These can be substituted into the first equation to give ...

  (b +6) +b +(5 +2b) = 55

  4b +11 = 55

  4b = 44

  b = 11

  a = b+6 = 17

  c = 5 +2b = 27

He booked 17 tickets on Airline A, 11 tickets on Airline B, and 27 tickets on Airline C.

Answer:

There is not enough information to determine the mean, the median is 28.

There is not enough information to determine the mean absolute deviation, the interquartile range is 18

Step-by-step explanation:

The box plot given has a skewed distribution, this means that both the mean and median values are not the same. From a box plot, the median value Can be obtained as the point in between the box.

From the box plot given, the marked point in between the box is 28 cm

Hence, Median = 28 cm

The mean cannot be inferred from the skewed box plot.

There is also not enough information to determine the mean absolute deviation ;

The interquartile range:

(Q3 - Q1)

Q3 = upper quartile, the endpoint of the box = 40

Q1 = the starting point of the box = 22

IQR = Q3 - Q1

IQR = 40 - 22 = 18

Answer:

13/16 miles per minute

Step-by-step explanation:

Take the miles and divide by the minutes

1/8 ÷ 2/13

Copy dot flip

1/8 * 13/2

13/16 miles per minute

Answer:

$4543.70

General Formulas and Concepts:

Pre-Algebra

Algebra I

Simple Interest Rate Formula: [tex]\displaystyle A = P(1 + rt)[/tex]

Step-by-step explanation:

Step 1: Define

Identify

P = 3500

t = 6

r = 4.97% = 0.0497

Step 2: Find Interest

Answer:

x=10

Step-by-step explanation:

Using the Rational Roots Test, we can say that the potential rational roots are

± (1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90).

Unfortunately, there doesn't really seem to be an easy way to figure out which numbers are actually roots outside of guess and check. Therefore, to solve this, we'll have to go through numbers until we hit something.

To make the process faster, I wrote a Python script as follows:

numbers = [1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90]

negative_numbers = [i * (-1) for i in numbers]

numbers = numbers + negative_numbers

for i in numbers:

   if (i**3 - 10*(i**2) + 9*i-90) == 0:

       print(i)

The result comes out as 10, meaning that 10 is our only rational root. Using the Factor Theorem, we can say that because 10 is a root, (x-10) is a factor of the polynomial. Using synthetic division, we can divide (x-10) from the polynomial to get

10 |   1     -10     9      -90

    |          10     0       90

    _________________

        1       0     9        0

Therefore, we can say that

(x³-10x²+9x-90)/(x-10) = (x²+0x+9), so

x³-10x²+9x-90 = (x-10)(x²+9)

As the only solution to x²+9=0 contains imaginary numbers, x=10 is the only solution to x³-10x²+9x-90 = (x-10)(x²+9) = 0

Hi there!

[tex]\large\boxed{x = 60^o}[/tex]

We know:

∠AGB ≅ ∠DGC because they are vertical angles. They both are 90°.

∠AGE ≅ FGC because they are vertical angles, equal 30°.

∠BGF ≅ ∠DGE are vertical angles, both equal x.

All angles sum up to 360°, so:

360° = 90° + 90° + 30° + 30° + x + x

Simplify:

360° = 240° + 2x

Subtract:

120°  = 2x

x = 60°

Answer:

R1 = 150 in = 12.5 ft

R2 = 170 in = 14.167 ft

H = 220 in = 18.333 ft

Volume of solid cylinder = Pi * R^2 * H

So the volume of a hollow cylinder must be V = Pi * H * (R2^2 - R1^2)

V = 3.142 * 18.33 * (14.17^2 - 12.5^2) = 2565 ft^3

.

Answer:

= 1296x √ xy

Step-by-step explanation:

Apply exponent rule: a^b . a^c = a^b + c    3 . 3 = 3^ 1 + 1

= x . 3^1+1 √648x . 4y . 8

Add the numbers: 1 + 1 = 2

= x . 3^2 √648x . 4y . 8

= 3^2 . 144x √ xy

Refine

= 1296x √ xy

9514 1404 393

Answer:

  $562,500 per hour

Step-by-step explanation:

The cost will be a minimum where C'(x) = 0.

 C'(x) = 0.56x -0.7 = 0

  x = 0.7/0.56 = 1.25

The cost at that production point is ...

  C(1.25) = (0.28×1.25 -0.7)1.25 +1 = -0.35×1.25 +1 = 0.5625

The minimum production cost is $562,500 per hour for production of 1250 items per hour.

_____

Additional comment

This is different than the minimum cost per item. This level of production gives a per-item cost of $450. The minimum cost per item is $358.30 at a production level of 1890 per hour.

Answer:

The car will depreciate at a rate of 21.14% per year.

Step-by-step explanation:

Given that the value of a car will “depreciate” over time, and, for example, a car that was worth $ 24,000 when it was new, is being sold for $ 13,500 three years later, to determine the annual depreciation rate on this car the following calculation must be performed:

13,500 x (1 + X) ^ 1x3 = 24,000

13,500 x (1 + 0.2114) ^ 3 = 24,000

X = 21.14%

Therefore, the car will depreciate at a rate of 21.14% per year.

Answer:

4*12*2

Step-by-step explanation:

it will be the right answer

Answer:

There are 6 boys in group.

Step-by-step explanation:

Since we have given that

Number of arrangement of 4 boys = 12 times the number of arrangement of 2 boys.

So, Let the number of boys in the group be 'x'.

So, Number of boys in the group will be

\begin{gathered}x=\frac{12\times 2}{4}\\\\x=\frac{24}{4}\\\\x=6\end{gathered}

x=

4

12×2

x=

4

24

x=6

Hence, there are 6 boys in the group.

hope it helps you a follow would be appreciated

Answer:

(a) 129600 J

(b) 81000 J

Step-by-step explanation:

The work done is given by the product of force and the displacement in the direction of force.

Force, F = 500 N

distance, d = 324 m

(a) friction force, f = 100 N

The work done is

W = (F - f) x d

W = (500 - 100) x 324

W = 129600 J

(b) Friction, f = 250 N

The work done is

W = (F - f) d

W = (500 - 250) x 324

W = 81000 J

9514 1404 393

Answer:

  3

Step-by-step explanation:

AB is 1 unit long.

A'B' is 3 units long.

The scale factor is the ratio of these lengths:

  scale factor = A'B'/AB = 3/1 = 3

ABC is dilated by a factor of 3 to get A'B'C'.