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A recent year was randomly picked from 1985 to the present. In that year, there were 2051 Hispanic students at Cabrillo College out of a total of 12,328 students. At Lake Tahoe College, there were 321 Hispanic students out of a total of 2441 students. In general, do you think that the percent of Hispanic students at the two colleges is basically the same or different? (Source: Chancellor’s Office, California Community Colleges, November 1994 )

Eight runners were convinced that the mean difference in their individual times for running one mile versus race walking one mile was at most 2 minutes. Below are their times. Do you agree that the mean difference is at most 2 minutes?

Running time (minutes) Race walking time (minutes)
5.1 7.3
5.6 9.2
6.2 10.4
4.8 6.9
7.1 8.9
4.2 9.5
6.1 9.4
4.4 7.9
  • t 7 size 12{t rSub { size 8{7} } } {}
  • t = 2 . 9850 size 12{t=2 "." "9850"} {}
  • 0.0102
  • Decision: Reject null; There is sufficient evidence to conclude that the mean difference is more than 2 minutes.

Marketing companies have collected data implying that teenage girls use more ring tones on their cellular phones than teenage boys do. In one particular study of 40 randomly chosen teenage girls and boys (20 of each) with cellular phones, the mean number of ring tones for the girls was 3.2 with a standard deviation of 1.5. The mean for the boys was 1.7 with a standard deviation of 0.8. Conduct a hypothesis test to determine if the means are approximately the same or if the girls’ mean is higher than the boys’ mean.

While her husband spent 2½ hours picking out new speakers, a statistician decided to determine whether the percent of men who enjoy shopping for electronic equipment is higher than the percent of women who enjoy shopping for electronic equipment. The population was Saturday afternoon shoppers. Out of 67 men, 24 said they enjoyed the activity. 8 of the 24 women surveyed claimed to enjoy the activity. Interpret the results of the survey.

  • 0.22
  • 0.4133
  • Decision: Do not reject null

We are interested in whether children’s educational computer software costs less, on average, than children’s entertainment software. 36 educational software titles were randomly picked from a catalog. The mean cost was $31.14 with a standard deviation of $4.69. 35 entertainment software titles were randomly picked from the same catalog. The mean cost was $33.86 with a standard deviation of $10.87. Decide whether children’s educational software costs less, on average, than children’s entertainment software. (Source: Educational Resources , December catalog)

Parents of teenage boys often complain that auto insurance costs more, on average, for teenage boys than for teenage girls. A group of concerned parents examines a random sample of insurance bills. The mean annual cost for 36 teenage boys was $679. For 23 teenage girls, it was $559. From past years, it is known that the population standard deviation for each group is $180. Determine whether or not you believe that the mean cost for auto insurance for teenage boys is greater than that for teenage girls.

  • z = 2 . 50 size 12{z=2 "." "50"} {}
  • 0.0063
  • Decision: Reject null

Questions & Answers

the relationship between two concept supply and Demand
Lebogang Reply
what is globalization
Nuertey Reply
what is the best definition of economic?
Humble Reply
what is aggregat demand in open economy
Dagim Reply
Aggregate demand is expressed as the total amount of money exchanged for those goods and services at a specific price level and point in time.
Bayou
What is the full meaning of GDP
Akinbulejo Reply
gross domestic product
Yanish
Gross Domestic Product
bode
Formula for calculating the percentage of change in price, quantity, price elasticity of demand
Augustina Reply
Given that the elasticity of supply for a good is 2 and the percentage change in price is 45%.What is the percentage change in quantity supplied
Mbe Reply
Please don't understand
Augustina
Explain
Adebisi
ok
Owoeye
percentage change should be 44%
Owoeye
state and explainfour function of a costumer service
Egba Reply
the circular flow model of the economy is a simplification showing how the economy works and the relationship between income,production and spending in the economy as a whole
Anna Reply
It is an idea that show us the way the economy works about their income, production, and spending in the economy
Augustina
what is circular flow
Ntokozo Reply
what is economics?
Dorcas Reply
Economics is defined as the science that study human behaviour as a relationship between ends and scarce means which have alternative uses.
Emmanuella
economics is a social science concerned with the production,distribution, and consumption of goods and services
Michael
Economics as a science studies human behaviour as a relationship between ends and scarce means with alternative use.
Augustina
economics can be defined as social science which studies human behavior as a relationship between ends and scare means which have alternative uses.... Lionel C Robins
Owoeye
in 2021 Amazon reduced the annual subscription fee for its prime membership service which provides free two_day shipping on many goods and other benefits, from $119 to $99. Zoppa consulting, an investment firm estimated that before the price reduction, prime had 62million subscribers globally. If so, what is the arc elasticity of demand for a prime membership.
Joan Reply
Differences between microeconomics and macroeconomics
tatiana Reply
Macroeconomics deal with the economy as a whole.that is an economy affect the firm ,government and the households eg.unemployment, whilst Microeconomics deal with the the decision making of households,firm and government separately.
Amah
Microeconomics is the branch of economic which studies the behaviour of individual households, firms and industries whiles macroeconomic studies the economy as a whole. It looks at the economy from a a broader perspective.
Augustina
what is Economics
Ebem Reply
the branch of knowledge concerned with the production, consumption, and transfer of wealth and has Influence by sociology!!!!
Ajay
Economics is the study of how humans make decisions when they want to fulfil their requirements and desires for goods, services and resources.
Abdullah
Economics is the study how humans make decisions in the faces of scarcity.
Rose
economic is the study of how human make decision in the fact of scarcity.
Toang
Economics is a social science which study human behavior as a relationship between earn and scarce mean which have alternative uses
Juliet
what is market structure
Fatima
market structure in economics depicts how firms are differentiated and categorised based on types of goods they sell and how their operations are affected by external factors and elements.
Nasir
what is economic theory
Madara
what is demand
Gooluck Reply
demand is the willingness to purchase something
Mohamed
demand is the potential ability or williness to purchases something at a particular price at a given period of time..
Ahmed
Demand refers to as quantities of a goods and services in which consumers are willing and able to purchase at a given period of time. Demand can also be defined as the desire backed by ability to purchase .
Fadiga
in a comparison of the stages of meiosis to the stage of mitosis, which stages are unique to meiosis and which stages have the same event in botg meiosis and mitosis
Leah Reply
Researchers demonstrated that the hippocampus functions in memory processing by creating lesions in the hippocampi of rats, which resulted in ________.
Mapo Reply
The formulation of new memories is sometimes called ________, and the process of bringing up old memories is called ________.
Mapo Reply
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Source:  OpenStax, Collaborative statistics (custom online version modified by t. short). OpenStax CNX. Jul 15, 2013 Download for free at http://cnx.org/content/col11476/1.5
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