susan bought 60 cookies. she shared 1/3 of them with her friends. how many cookies did she have left?

True or False; In spherical geometry, there is only one equilateral triangle.

Elodia [21]

It's true. It must equal 180 degrees and the only way to accomplish that while it being an equilateral triangle is by having only one triangle! :)

3 0

2 years ago

steve gaimes is paid overtime for all time worked past 40 hours in a week. his regular time pay rate is $12 an hour and his over

Elena-2011 [213]

Answer:

40 hours

Step-by-step explanation:

47.3-40= 7.3

He worked 7.3 hours overtime meaning he worked 40 regular hours.

6 0

2 years ago

The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus Sample Size Sample Mean Po

Leona [35]

Answer:

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

$p_v =P(Z>3.37)=1-P(Z$

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 mean for the Campus 1 is significantly higher than the mean for the group 2.

Step-by-step explanation:

Data given

Campus Sample size Mean Population deviation

1 330 33 8

2 310 31 7

$\bar X_{1}=33$ represent the mean for sample 1

$\bar X_{2}=31$ represent the mean for sample 2

$\sigma_{1}=8$ represent the population standard deviation for 1

$\sigma_{2}=7$ represent the population standard deviation for 2

$n_{1}=330$ sample size for the group 1

$n_{2}=310$ 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 the mean for Campus 1 is higher than the mean for Campus 2, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{2}\leq 0$

Alternative hypothesis: $\mu_{1} - \mu_{2}> 0$

We have the population standard deviation's, and the sample sizes are large enough we can apply a z test to compare means, and the statistic is given by:

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

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

P value

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

$p_v =P(Z>3.37)=1-P(Z$

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 mean for the Campus 1 is significantly higher than the mean for the group 2.

5 0

2 years ago

For today only I authorize you to offer a free insurance plan for one year to go to Mission signer for service dangerously in re

alukav5142 [94]

Answer:

1920

Step-by-step explanation:

7 0

1 year ago

Which statements about the factors of the terms in the expression 20 a + 15 a b + 24 b are true? Select three options.

ExtremeBDS [4]

Answer:

Following are the true statements

2. The factors common to 20a and 15ab are 1, 5, and a.

3. The factors common to 20a and 24b are 1, 2, and 4.

5. The GCF of the expression is 1

Step-by-step explanation:

Expression is 20a + 15ab + 24b

Now lets have a look at each of the options provided!

1. The factors common to 20a and 15ab are 1, 5, a, and b.

False

As you can see there is no b in 20a term only 1,5,a are common hence it is false.

2. The factors common to 20a and 15ab are 1, 5, and a.

True

The terms 20a and 15ab are divisible by 1,5,a hence it is true.

3. The factors common to 20a and 24b are 1, 2, and 4.

True

The terms 20a and 24b are divisible by 1,2,4 hence it is true

4. The GCF of the expression is ab.

False

20a + 15ab + 24b

As you can see ab is not common in all of the terms hence it cannot be greatest common factor

5. The GCF of the expression is 1

True

Factor of 20 are: 2,2,5,1

Factor of 15 are: 3,5,1

Factor of 24 are: 2,2,2,3,1

As you can see the only common factor among all the terms is 1 hence GCF is 1.

5 0

2 years ago