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
givi [52]
3 years ago
12

A sociologist studying the difference in ages between husbands and wives obtained a random sample of 55 married couples. The mea

n of the husbands’ ages was 38.5 years with standard deviation 12.6 years. The mean of the wives’ ages was 36.9 years with standard deviation 12.4 years. The sociologist calculated the difference between the ages for each couple. The mean difference was 1.6 years with standard deviation 2.1 years. A matched-pairs hypothesis test will be performed to investigate whether the difference is significant.
Mathematics
1 answer:
zalisa [80]3 years ago
8 0

Answer:

2.1/√55

Step-by-step explanation:

simga divided by sample size

You might be interested in
Select the expression that is equal and o (9x+3) - (5x-7)
MArishka [77]

Answer: D

Step-by-step explanation:

4 0
3 years ago
A data set includes 103 body temperatures of healthy adult humans having a mean of 98.3degreesF and a standard deviation of 0.73
faust18 [17]

Answer:

CI = (98.11 , 98.49)

The value of 98.6°F suggests that this is significantly higher

Step-by-step explanation:

Data provided in the question:

sample size, n = 103

Mean temperature, μ = 98.3

°

Standard deviation, σ = 0.73

Degrees of freedom, df = n - 1 = 102

Now,

For Confidence level of 99%, and df = 102, the t-value = 2.62      [from the standard t table]

Therefore,

CI = (Mean - \frac{t\times\sigma}{\sqrt{n}},Mean + \frac{t\times\sigma}{\sqrt{n}})

Thus,

Lower limit of CI =  (Mean - \frac{t\times\sigma}{\sqrt{n}})

or

Lower limit of CI =  (98.3 - \frac{2.62\times0.73}{\sqrt{103}})

or

Lower limit of CI = 98.11

and,

Upper limit of CI =  (Mean + \frac{t\times\sigma}{\sqrt{n}})

or

Upper limit of CI =  (98.3 + \frac{2.62\times0.73}{\sqrt{103}})

or

Upper limit of CI = 98.49

Hence,

CI = (98.11 , 98.49)

The value of 98.6°F suggests that this is significantly higher and  the mean temperature could very possibly be 98.6°F

7 0
3 years ago
If a cell has a volume of 3nm, what are the surface area and the volume of the cell?
harkovskaia [24]
A cell has a radius: r = 3 nmThe surface area of a cell:A = 4 r² π = 4 · 3² π = 4 · 9 π = 36 π nm²The volume of a cell:V = 4/3 r³ π = 4/3 · 3³ π = 4 · 9 π = 36 π nm³Answer: The surface area is 36 π nm² and the volume is 36 π nm³.
7 0
3 years ago
A rock is thrown into the air. The height of the rock is modeled by s(t) = −16tଶ + 64t + 80 feet for t ≥ 0 seconds. The rock hit
ExtremeBDS [4]

Answer:

144 feets

Step-by-step explanation:

Look on s(t) like quadratic function. We need to find maximum of the function using 1st diferetioal:

s(t)=-16t^2+64t+80

s’(t)=-32t+64

S’(t)=0 if t=2

For t>2, s’(t)<0

For t<2, s’(t)>0. So the maximum od function is in the point 2.

S(2)=-16*4+64*2+80=-64+128+80=144

6 0
3 years ago
Hannah and Sarah are on a car trip. They take a break after traveling 55 miles. They are 15 miles short of being only 1/4 of the
Ray Of Light [21]

Answer:

55+14=69

69x4=d

d=276

Step-by-step explanation:

its simple math really

8 0
3 years ago
Other questions:
  • Please help me with this math problem.
    5·1 answer
  • Subtract. (5x2−3x−2)−(−2x2−x+10) Express the answer in standard form. Enter your answer in the box.
    6·2 answers
  • Anita runs 5/8 mile everyday. How many miles does she run in 5 days?
    13·2 answers
  • What is 9/16 rounded to the nearest whole number?
    6·1 answer
  • Please help and show work if you can I only need 10, 11 and 12​
    7·1 answer
  • Is 16 tons greater then less then or equal to 32000 ib​
    10·1 answer
  • 1 A camera is capable of snapping 3/4 of a picture per second. How many pictures can be snapped within a 36-second period?
    7·1 answer
  • Can someone please help me on this? thanks!!
    13·1 answer
  • PLEASE HELP I WILL GIVE BRAINLIEST
    14·1 answer
  • Roger could fit seven action figures on each shelf in his room. His room has two shelves. How many action figures total could hi
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!