answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
sveticcg [70]
1 year ago
10

Katrina randomly selected 64 students out of her school of 400 students and found that 40 of them want school to start at a late

r time.
With a desired confidence of 99%, which has a z*-score of 2.58, which statements are true? Check all that apply.

E = z*

The sample size is 40.
The sample size is 64.
The point estimate of the population proportion is 0.16.
The point estimate of the population proportion is 0.625.
The margin of error is approximately 12%.
The margin of error is approximately 16%.
Mathematics
2 answers:
SashulF [63]1 year ago
6 0

- The sample size is 64.

- The point estimate of the population proportion is 0.625.

-The margin of error is approximately 16%.

Svetllana [295]1 year ago
4 0

Answer:

Step-by-step explanation:

Given that Katrina randomly selected 64 students out of her school of 400 students and found that 40 of them want school to start at a later time.

Out of the statements given the true statements are :

1) The sample size is 64

2) The point estimate of the population is sample proportion =40/64 =5/8

=0.625

3) Margin of error = std error x 2.58

Std error = sq rt pq/n

p=0.625 and q = 0.375

Hence std error = 0.060

Margin of error = 0.156

Round off to 0.16 = 16%

You might be interested in
There are two approaches to solving the equation -3x + 10 = 4x - 20 Subtract 4x from both sides. OR Add 3x to both sides. –7x +
Scrat [10]

<u>Answer:</u>

There are two approaches to solving the equation -3x + 10 = 4x - 20. The value of x after solving in both methods is 4.2857.

<u>Solution:</u>

Given, equation is -3x + 10 = 4x – 20.

We have to solve the given equation in two methods, now let us see the first method.

<u><em>1st method ⇒ by subtracting 4x from both sides.</em></u>

Then, -3x + 10 = 4x – 20 ⇒ -3x + 10 – 4x = 4x – 20 – 4x ⇒ -3x – 4x = -20 – 10 ⇒ -7x = -30 ⇒ 7x = 30  

Then, x = \frac{30}{7}

Now, let us use the 2nd method.

<em><u>2nd method ⇒ by adding 3x on both sides.</u></em>

Then, -3x + 10 = 4x – 20 ⇒ -3x + 10 + 3x = 4x – 20 + 3x

⇒ 10 + 20 = 4x + 3x

⇒ 7x = 30

⇒ x = \frac{30}{7}

Hence, the value of x after solving in both methods is \frac{30}{7} = 4.2857.

6 0
1 year ago
Read 2 more answers
Joan is building a sandbox in the shape of a regular pentagon. The perimeter of the pentagon is 35y4 – 65x3 inches. What is the
PIT_PIT [208]
From the choices above the answer would be: D 7y^4-13x^3 inches
8 0
2 years ago
Read 2 more answers
Barbara drives between Miami, Florida, and West Palm Beach, Florida. She drives 50 mi in clear weather and then encounters a thu
NeX [460]

Distance traveled in clear weather = 50 miles

Distance traveled in thunderstorm = 15 miles

Let speed in clear weather = x

⇒ Speed in thunderstorm = x-20

Total time taken for trip = 1.5 hours

We need to determine average speed in clear weather (i.e. x) and average speed in the thunderstorm (i.e. x-20 ).

Total time taken for trip = Time taken in clear weather + Time taken in thunderstorm

⇒ Total time taken for trip = \frac{Distance covered in clear weather}{Speed in clear weather} + \frac{Distance covered in thunderstorm}{Speed in thunderstorm}

⇒ 1.5 = \frac{50}{x} + \frac{15}{x-20}

⇒ 1.5 = \frac{50(x-20)+15(x)}{(x)(x-20)}

⇒ 15*x*(x-20) = 10*[50*(x-20)+15*x]

⇒ 15x² - 300x = 500x - 10,000 + 150x

⇒ 15x² - 300x = 650x - 10,000

⇒ 15x² - 950x + 10,000 = 0

⇒ 3x² - 190x + 2,000 = 0

The above equation is in the format of ax² + bx + c = 0

To determine the roots of the equation, we will first determine 'D'

D = b² - 4ac

⇒ D = (-190)² - 4*3*2,000

⇒ D = 36,100 - 24,000

⇒ D = 12,100

Now using the D to determine the two roots of the equation

Roots are: x₁ = \frac{-b+\sqrt{D}}{2a} ; x₂ = \frac{-b-\sqrt{D}}{2a}

⇒ x₁ = \frac{-(-190)+\sqrt{12,100}}{2*3} and x₂ = \frac{-(-190)-\sqrt{12,100}}{2*3}

⇒ x₁ = \frac{190+110}{6} and x₂ = \frac{190-110}{6}

⇒ x₁ = \frac{300}{6} and x₂ = \frac{80}{6}

⇒ x₁ = 50 and x₂ = 13.33

So speed in clear weather can be 50 mph or 13.33 mph. However, we know that in thunderstorm was 20 mph less than speed in clear weather.

If speed in clear weather is 13.33 mph then speed in thunderstorm would be negative, which is not possible since speed can't be negative.

Hence, the speed in clear weather would be 50 mph, and in thunderstorm would be 20 mph less, i.e. 30 mph.

7 0
2 years ago
PLEASE HURRY WILL GIVE BRAINLIEST! Which phrase describes the algebraic expression Three-fourths x + 2? A. three-fourths of a nu
Jlenok [28]

Answer: A

Step-by-step explanation:

3/4x+2

3/4+2

7 0
2 years ago
Read 2 more answers
15) Bob has 12 black pen, 14 red pen, 15 green pens, 24 blue pens and 3 boxes of
cricket20 [7]

Answer:

13, 16, 18

Step-by-step explanation:

Sabemos que podemos calcular el total de plumas amarillos, por medio de la media.

16 = (12 + 14 + 15 + 24 + x + y + z) / 7

16 * 7 = 12 + 14 + 15 + 24 + x + y + z

112 = 65 + x + y + z

x + y + z = 112-65

x + y + z = 47

sabemos que la mediana es el valor medio, y que ese 46 debe dividirse entre 3 valores porque son 3 cajas, entonces debemos buscar los números adecuados para el valor 15 esté en la mitad, es decir de cuarto.

Sin meter los valores nuevos, el ranking sería así:

12

14

15

24

el 15 esta de tercero, para que quede de cuarto, debe tener dos valores por debajo y un por arriba, así:

X

12

14

15

y

z

24

Por lo tanto, valores mayores a 15 serían por ejemplo y = 16 y z = 18:

16 + 18 = 34

x = 47-34 = 13

quedaría:

12

13

14

15

dieciséis

18 años

24

Si recalculamos la media:

m = (12 + 14 + 15 + 24 + 13 + 16 + 18) / 7 = 16

8 0
1 year ago
Other questions:
  • After dinner 2/3 of the corn bread is left suppose 4 friends want to share it equally. What fraction names how much of whole pan
    13·2 answers
  • M∠AFD=90°. m∠AFB=31°. Find m∠CFEm.
    14·2 answers
  • Find the number of ordered quadruples (a, b, c,
    10·1 answer
  • A rectangle that had the perimeter of 70 and the area of 250 has enlarged; its sides became twice as long. what is the new area
    10·1 answer
  • A field has an area of 9/20 square mile. find the width of the fieldif the length is 10/9 mile long
    10·1 answer
  • Which expression is equivalent to StartRoot StartFraction 25 x Superscript 9 Baseline y Superscript 3 Baseline Over 64 x Supersc
    8·2 answers
  • Jakob wants to invite 20 friends to his birthday, which will cost his parents $250. If he decides to invite 15 friends instead,
    11·2 answers
  • I NEED HELP . I'm having trouble trying to figure out how to answer this can anyone help please?
    13·1 answer
  • This chart shows what happens when each object is placed on a balance with a 10 kg weight on the other side.
    5·2 answers
  • Which statements are true about David's work? Check all that apply. The GCF of the coefficients is correct. The GCF of the varia
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!