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sleet_krkn [62]

3 years ago

5

if you randomly select a student from local gymnastic class, the probability that you select a 10-year old is 0.4. If there are

fourteen 10 year-old, how many student must be in the class

1 answer:

Travka [436]3 years ago

5 0

35 people! pls mark as brainliest

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Does combine mean add?

spin [16.1K]

Combine does mean add

7 0

3 years ago

A school will offer pizza on Friday's if at least 30% of the students will buy it. A sample of 50 students asked if they would b

Whitepunk [10]

Answer:

0.0614

Step-by-step explanation:

Solution:-

- The school offers pizza on friday when at-least 30% students are willing to buy.

- The minimum required proportion of students, p = 30%

- A sample of n = 50 students were taken and out of the sample x = 10 people responded willing to buy pizza.

- We will denote a random variable X: the number of students willing to buy Pizza on fridays.

- For the sample of n = 50, for Pizza to be offered on friday the expected number of student who should opt for buying must be at-least:

Expected ( Mean - u ) = n*p = 50*0.3 = 15 people.

- The standard deviation for the normal distribution can be determined as follows:

standard deviation ( s ) = √n*p*(1-p)

= √50*0.3*(0.7)

= √10.5 = 3.2404

- We will assume that the random variable X follows normal distribution:

X ~ Norm ( 15 , 3.2404^2 )

- To determine the probability of sample of size n = 50 with proportion or lower. The number of people willing to buy pizza on friday as per survey are x = 10.

- Evaluate the standard normal ( Z-score ):

P ( X < x ) = P ( Z < ( x - u ) / s )

P ( X < 10 ) = P ( Z < ( 10 - 15 ) / 3.2404 )

P ( X < 10 ) = P ( Z < -1.54301 )

- Use the standard normal tables to determine the value of P ( Z < -1.54301 ):

P ( X < 10 ) = P ( Z < -1.54301 ) = 0.0614

Answer: The probability of getting a sample with the proportion or lower given a population with a proportion of .30 is 0.0614.

5 0

3 years ago

Tanya's father travels every week for business. He has traveled around the

Nikitich [7]

The correct answer would be: 4.6 x 10^5

8 0

2 years ago

Please use system of linear equations by elimination OR substitution. I need the work as well please.

Olin [163]

1) P= 64 cm, width = x, length = 14 + x

64 = x + x + 14 + x + 14 + x

64 = 4x + 28

4x = 64 - 28

4x = 36

x = 36/ 4

x = 9

AREA = 9 x (9+14)

Area = 9 x 23

Area = 207 cm

2) smaller no. = y, bigger no. = x

x - y = 3

2x+1/2y=36

Next, multiply 2 to first equation and find y:

2x-2y=6

5/2y=30

y = 12

Substitue y to x-y=3 to find x,

x = 15

3) x = pencil, y = pen

5x + 4y = $6.15

8x + 3y = 9.85$

8x + 7y = ?

5x + 4y = 6.15$ multiply both sides by -3

8x + 3y = 9.85$ multiply both sides by 4

-15x + 32x = (-3)*6.15 + 4*9.85

7x = 19.87 multiply both sides by 8/7

8x = (8/7) x 19.87

Add both equations:

32y - 15y = 8x6.15 - 5*9.58

17y = 1.3

y = 91/17) x 1.3

7y = (7/17)x 1.3

8x + 7y = (8/7) x 19.87 + (7/17) x 1.3

8x + 7y = $23.244

4) 2l + 2w = 0

2 x 2l + 2 x 1/2w = 40 + 16

l+w = 20

4l+w = 56

I’ve got l = 12 and w = 8

5) answer: 28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° = \frac{ab}{bc}

but bc = 20 feet.

⇒ tan 55 ° = \frac{ab}{20}

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348 ≈ 28.56 feet

6) The answer is teh attachment !

7) 3x-x+2=4

HOPE THE ANSWERS HELP!! PL MARK ME BRAINLIEST!

3 0

2 years ago

A farmer had twice as many chickens as ducks on his farm. After he sold 166 chickens and ducks, he had half as many chickens as

mamaluj [8]

Answer:

The farmer have at first <u>202</u> chickens.

Step-by-step explanation:

Given:

A farmer had twice as many chickens as ducks on his farm. After he sold 166 chickens and ducks, he had half as many chickens as ducks left.

Now, to find the chickens farmer have at first.

Let the chickens be $x.$

And, the ducks be $y.$

<em>As, the farmer had twice as many chickens as ducks on his farm.</em>

So, $x=2y$ ......(1)

<em>As, given the farmer after selling 166 chickens and ducks, he had half as many chickens as ducks left.</em>

According to question:

$x-166=(y-29)\times \frac{1}{2}$

$x-166=\frac{y-29}{2}$

Substituting the value of $x$ from equation (1) we get:

$2y-166=\frac{y-29}{2}$

<em>By cross multiplying we get:</em>

$4y-332=y-29$

<em>Adding both sides 332 we get:</em>

$4y=y+303$

<em>Subtracting both sides by </em> $y$ <em> we get:</em>

$3y=303$

<em>Dividing both sides by 3 we get:</em>

$y=101.$

Now, to get the number of chickens substituting the value of $y$ in equation (1):

$x=2y\\\\x=2\times 101\\\\x=202.$

Therefore, the farmer have at first 202 chickens.

7 0

3 years ago