1answer.
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
aivan3 [116]
3 years ago
13

A sample of 12 measurements has a mean of 38 and a sample standard deviation of 4.25. Suppose that the sample is enlarged to 14

measurements, by including two additional measurements having a common value of 38 each. The sample standard deviation of the 14 measurements is:
Mathematics
1 answer:
Ierofanga [76]3 years ago
5 0

Answer:

The sample standard deviation of the 14 measurements is 3.93

Step-by-step explanation:

The standard deviation = √(variance)

The standard deviation is the square root of variance. And variance is an average of the squared deviations from the mean.

Mathematically,

Standard deviation = σ = √[Σ(x - xbar)²/N]

x = each variable

xbar = mean

N = number of variables

For 12 variables,

N = 12

σ = 4.25

xbar = 38

Σ(x - xbar)² = sum of the square of all deviations; let it be equal to D

4.25 = √[Σ(x - xbar)²/12]

4.25 =√(D/12)

4.25² = D/12

D = 216.75.

For 14 measurements,

N = 14

The mean is going to still be 38, because the two new measurements are each 38.

xbar = 38

And the new additions to the sum of deviations, will be (38 - 38)² twice, that is, 0.

Standard deviation for 14 measurements

Standard deviation = σ = √[Σ(x - xbar)²/N]

σ = √(216.75/14) = 3.93

You might be interested in
Jazmin takes a ride share service home from the airport. The ride share service charges $5 as an initial cost to pick her up, an
Anon25 [30]

Answer:

38.75 = 2.25 m + 5

Step-by-step explanation:

It is given that :

Jazmin took a ride share service from airport to home.

The total cost of the ride service from airport to home is = $ 38.75

The ride service charged an initial cost for picker Jazmin = $ 5

Cost of the ride service for every mile = $ 2.25 per mile

Let the number of miles = m

Therefore, the equation that represents the situation is :

38.75 = 2.25 m + 5

where, m represents the number of miles.

6 0
2 years ago
The vertices of a triangle are A(1, –9), B(0, –3), C(–4, –5). Fine the length of each side. What type of triangle is triangle AB
Alenkinab [10]

Answer:

AB = √37

BC = 2√5

AC = √41

Type: SCALENE TRIANGLE

Step-by-step explanation:

Given the coordinates

A(1, –9), B(0, –3), C(–4, –5)

We are to find the length of each sides first. Using the formula for calculating the distance between two points, we will have;

For A(1, –9) and B(0, –3)

AB = √(-3+9)²+(0-1)²

AB = √6²+(-1)²

AB = √36+1

AB = √37

For coordinates B(0, –3) and C(–4, –5)

BC = √(-5+3)²+(-4-0)²

BC= √(-2)²+(-4)²

BC = √4+16

BC = √20

BC = 2√5

For coordinates  A(1, –9), C(–4, –5)

AC = √(-5+9)²+(-4-1)²

AC= √(4)²+(-5)²

AC = √16+25

AC = √41

<em>Since the sides of the triangles are all different, hence the triangle is a SCALENE triangle</em>

8 0
3 years ago
Convert the percent to a decimal, and then divide. 7% ÷ 4
Inessa05 [86]
7% = 0.07
0.07/4 = 0.0175

The answer is 0.0175
3 0
3 years ago
Read 2 more answers
Henry is an avid reader.He devours 90 pages in half-an-hour.How many pages has Henry read per minute?
ICE Princess25 [194]

Answer:

3 pages per minute

Step-by-step explanation:

Half an hour is eqquivalent to 30 minutes, so we do 90 (pages) / 30 (minutes) = 3--> Wich means that Henry can read 3 pages per minute.

4 0
3 years ago
Read 2 more answers
Rectangle R has varying length l and width w but a constant perimeter of 4 ft. A. Express the area A as a function of l. What do
ivanzaharov [21]
Given:
l = length of the rectangle
w = width of the rectangle
P = 4 ft, constant perimeter

Because the given perimeter is constant,
2(w + l) = 4
w + l = 2
w = 2 - l            (1)

Part A.
The area is
A = w*l 
   = (2 - l)*l
 A  = 2l - l²
This is a quadratic function or a parabola.

Part B.
Write the parabola in standard form.
A = -[l² - 2l]
   = -[ (l -1)² - 1]
   = -(l -1)² + 1
This is a parabola with vertex at (1, 1). Because the leading coefficient is negative the curve is downward, as shown below.

The maximum value occurs at the vertex, so the maximum value of A = 1.
From equation (1), obtain
w = 2 - l = 2 - 1 = 1.
The maximum value of the area occurs when w=1 and l=1 (a square).

Answer:
The area is maximum when l=1 and w=1.
The geometric argument is based on the vertex of the parabola denoting maximum area.

4 0
3 years ago
Other questions:
  • Use the Law of Cosines to find y. Round to the nearest tenth.
    11·1 answer
  • Factor k2 - 81. I would love it if someone could help me
    8·2 answers
  • Solve for g. 9+3.5g=11-0.5g
    5·2 answers
  • A pond is being drained by a pump. After 3 hours, the pond is half empty. A second pump is put into operation and together the t
    13·2 answers
  • 3 – 2x ≥ 5 or 3(x – 2) + 1 &gt; 7
    8·2 answers
  • You have a coin bank in the shape of a cylinder. It has a radius of 2 inches and a height of 6 inches. What is the surface area
    5·1 answer
  • The area of a rectangle is 3/5 square meter. The width is 2/5 meter. A. What is the length of the rectangle? Write your answer a
    6·1 answer
  • How do i graph x+3y=−12?
    6·1 answer
  • Evaluate 5v + w for v = 4 and w = 16. Show work.
    12·1 answer
  • Pleasee helpp answer correctly !!!!!!!!!! Will mark Brianliest !!!!!!!!!!!!!!!!!!
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!