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
notsponge [240]
3 years ago
12

The power takeoff driveline on tractors used in agriculture is a potentially serious hazard to operators of farm equipment. The

driveline is covered by a shield in new tractors, but for a variety of reasons, the shield is often missing on older tractors. Two types of shields are the bolt-on and the flip-up. It was believed that the bolt-on shield was perceived as a nuisance by the operators and deliberately removed, but the flip-up shield is easily lifted for inspection and maintenance and may be left in place. In a study initiated by the U.S. National Safety Council, random samples of older tractors with both types of shields were taken to see what proportion of shields were removed. Of 183 tractors designed to have bolt-on shields, 35 had been removed. Of the 136 tractors with flip-up shields, 15 were removed. We wish to perform a test of H0: pb = pf versus Ha: pb pf where pb and pf are the proportions of all tractors with the bolt- on and flip-up shields removed, respectively. Which of the following conditions for performing the appropriate significance test is definitely not satisfied in this case?
(a) Both populations are Normally distributed.
(b) The data come from twp independent samples
(c) Both samples were chosen at random.
(d) The counts of successes and failures are large enough to use Normal calculations.
(e) Both populations are at least 10 times the corresponding sample sizes
Mathematics
1 answer:
Roman55 [17]3 years ago
5 0

Answer:

(a) Both populations are Normally distributed.

Step-by-step explanation:

Hello!

There are two types of shields in older tractors, bolt-on shield, and flip-up shield. The researcher wants to study the proportion of older tractors whose shields were removed. For these two random samples where taken, one of older tractors with bolt-on shields and the other one of older tractors with flip-up shields, the number of tractors whose shields were removed was recorded in both groups.

Sample 1: bolt-on

nb= 183

xb= 35 with removed shields

pb'= 35/183= 0.19

Sample 2: flip-up

nf= 136

xf= 15 with removed shields

pf'= 15/136= 0.11

Statistic hypotheses:

H₀: pb=pf

H₁: pb≠pf

(a) Both populations are Normally distributed. d) The counts of successes and failures are large enough to use Normal calculations.

The populations are not normal, these are two binomial populations.

To be able to use the normal calculations the following conditions should be met:

Population 1

n₁≥30 ⇒ nb= 183

n₁*p₁'≥5 ⇒ nb*pb'= 183*0.19= 34.77

n₁*(1-p₁')≥5 ⇒ nb*(1-pb')= 183*(1-0.19)= 148.23

Population 2

n₂≥30 ⇒ nf= 136

n₂*p₂'≥5 ⇒ nf*pf'= 136*0.11= 14.96

n₂*(1-p₂')≥5 ⇒ nf*(1-pf')= 136*(1-0.11)= 121.04

(b) The data come from two independent samples (c) Both samples were chosen at random.

Both conditions are met, the samples are randomly selected, the randomization included in the sampling method guarantees the independence between the samples.

(e) Both populations are at least 10 times the corresponding sample sizes

Without the information regarding the populations, you'll have to assume that the population of old tractors with bolt-on shields is greater than 1830 and the population of old tractors with flip-up shields is greater than in 1360.

I hope this helps!

You might be interested in
A town's population has been growing linearly. In 2003 the population was 47,000. The population has been growing by 1200 people
blsea [12.9K]

Answer:

Step-by-step explanation:

The population in 2003= 47000

Since the population increase by 1200 every year,

in 2004 the population will be 47000+1200

in 2005 the population will be 47000+(1200+1200) which is the same as

47000+2(1200) where 2 is 2 years after 2003,

Therefore the population x years after 2003 is 47000+x(1200).

P= 47000+1200x

b) The population at 2009 which is 6 years after 2003 will be

47000+(1200)*6=47000+7200= 54200

The population at 2009 is 54200,

7 0
3 years ago
The volume for a rectangular prism is given by the formula V = l · w · h, where l is the length of the prism, w is the width of
Charra [1.4K]

Answer:

4

Step-by-step explanation:

devide 144 by 9

get 16

The base squared is 16

find the root of 16

get 4

4 is your awnser

4 0
3 years ago
Someone please help me please
sertanlavr [38]

Answer:

D.   (x - 2)(x + 2)

Step-by-step explanation:

Look at the graph, when y = 0, x = - 2 and x = 2, vertex = -4

OK so x = -2 means x + 2 = 0

and x = 2, means x - 2 = 0

So

answer :D.  (x - 2)(x + 2)

7 0
3 years ago
Find the simplified product where sqrt 5x ( sqrt 8x^2 - 2 sqrt x)
alukav5142 [94]

Answer:

40x^3 -10x

Step-by-step explanation:

Used math-way to solve this! I'm sorry if wrong, x

3 0
3 years ago
Read 2 more answers
Decimal equivalente para 13/25
Annette [7]

Answer:

0.52

Step-by-step explanation:

(13/25)(4/4)=52/100

52/100=0.52

4 0
3 years ago
Read 2 more answers
Other questions:
  • Mei is writing 4.28 as a mixed number. Find her mistake and correct it.
    5·2 answers
  • Hurry please!! Use any model you choose to solve the story problem. Zoey found that box of dog food was left in the pantry. She
    12·1 answer
  • What is the approximate value of x in the diagram below?
    11·2 answers
  • The graph of an ellipse is shown. which equation represents this ellipse?
    7·2 answers
  • NEED HELP ASAP!!!<br> due by 3
    8·2 answers
  • Demarcus went out to dinner at a restaurant with his family. Their bill, including tax, totaled $32. If the family wants to leav
    5·1 answer
  • What would John pay for a CD player that sells for $550<br>is discounted by 15%?​
    7·1 answer
  • Please help me<br> If you give me a good answer I will award brainiest
    10·2 answers
  • 18 POINTS for finding 18 ANGLES on parallel lines and transversal
    15·2 answers
  • Given that f (x) = x^2 - 5x and g (x) x + 4
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!