Mathematics, 06.12.2019 02:31 lenaeeee

Arandom sample of 100 people from city a has an average iq of 120 with a sd of 18. independently of this, a random sample of 150 people from city b has an average iq of 116 with a sd of 15. are residents of city a smarter on average? make a z-test of the difference in average iqs; the null hypothesis is that there is no difference.

Answers: 2

Show answers

Answers

Answer from: keshewar4427

$z=\frac{(120-116)-0}{\sqrt{\frac{18^2}{100}+\frac{15^2}{150}}}}=1.837$

p_v =P(z1.837)=1-P(Z

Comparing the p value with a significance level for example $\alpha=0.05$ we see that p_v so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that the average IQ on city A is signficantly higher than city B at 5% of singificance.

Step-by-step explanation:

$\bar X_{A}=120$ represent the mean for sample 1

$\bar X_{B}=116$ represent the mean for sample 2

$s_{A}=18$ represent the sample standard deviation for 1

$s_{B}=15$ represent the sample standard deviation for 2

$n_{A}=100$ sample size for the group 2

$n_{B}=150$ sample size for the group 2

$\alpha$ Significance level provided

z would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if residents of City A smarter on average, the system of hypothesis would be:

Null hypothesis: $\mu_{A}-\mu_{B}\leq 0$

Alternative hypothesis: $\mu_{A} - \mu_{B} 0$

We don't have the population standard deviation's, but the sample sizes are large enough we can apply a z test to compare means, and the statistic is given by:

$z=\frac{(\bar X_{A}-\bar X_{B})-\Delta}{\sqrt{\frac{s^2_{A}}{n_{A}}+\frac{s^2_{B}}{n_{B}}}}$ (1)

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

With the info given we can replace in formula (1) like this:

$z=\frac{(120-116)-0}{\sqrt{\frac{18^2}{100}+\frac{15^2}{150}}}}=1.837$

P value

Since is a one right tailed test the p value would be:

p_v =P(z1.837)=1-P(Z

Answer from: Quest

$22. if larry's profit were to minimize by one for every hour his store were to be closed, we would subtract 30 by 8.

Answer from: Quest

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.

Another question on Mathematics

Mathematics, 21.06.2019 15:20

The speed of a falling object increases at a constant rate as time increases since the object was dropped. which graph could represent the relationship betweent time in seconds, and s, speed in meters per second? speed of a falling object object over time

Answers: 1

Answer

Mathematics, 21.06.2019 16:30

Pete is making decorations for a dinner party. the instructions tell him to use 9 flowers for a medium-sized decoration. complete each statement to adjust the flowers for different-sized decorations based on these instructions.

Answers: 3

Answer

Mathematics, 21.06.2019 17:00

Determine the fraction of total interest owed. after the fourth month of a 12-month loan: the numerator is: {(n + ) + (n + ) + (n + ) + (n + )} = , and the denominator is: {(n) + (n + 1) + + (n + )} = . therefore, the fraction is numerator/denominator (to the nearest tenth) =

Answers: 1

Answer

Mathematics, 21.06.2019 22:30

We have 339 ounces of jam to be divided up equally for 12 people how muny ounces will each person get

Answers: 1

Answer

You know the right answer?

Arandom sample of 100 people from city a has an average iq of 120 with a sd of 18. independently of...

Questions

Mathematics, 23.11.2020 17:00

Please help me figure this out ...