What is the value of n! 9×27+2×31-28=n

A gardener needs to move 2,782 pounds of dirt. He can carry 96 pounds in his wheelbarrow. How many trips will he need to make wi

svp [43]

Answer:

28.9

Step-by-step explanation:

2782 divied by 96 gives you 28.9.

7 0

3 years ago

A random sample of 49 measurements from one population had a sample mean of 15, with sample standard deviation 5. An independent

kotykmax [81]

Answer:

Comparing the p value with the significance level $\alpha=0.01$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and the difference between the two groups is significantly different.

Step-by-step explanation:

$\bar X_{1}=15$ represent the mean for sample 1

$\bar X_{2}=18$ represent the mean for sample 2

$s_{1}=5$ represent the sample standard deviation for 1

$s_{f}=6$ represent the sample standard deviation for 2

$n_{1}=49$ sample size for the group 2

$n_{2}=64$ sample size for the group 2

$\alpha=0.01$ Significance level provided

t would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the difference in the population means, the system of hypothesis would be:

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

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

We don't have the population standard deviation's, so for this case is better apply a t test to compare means, and the statistic is given by:

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

And the degrees of freedom are given by $df=n_1 +n_2 -2=49+64-2=111$

t-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:

$t=\frac{(15-18)-0}{\sqrt{\frac{5^2}{49}+\frac{6^2}{64}}}}=-2.897$

P value

Since is a bilateral test the p value would be:

$p_v =2*P(t_{111}$

Comparing the p value with the significance level $\alpha=0.01$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and the difference between the two groups is significantly different.

7 0

3 years ago

What is 3% in decimal form

AfilCa [17]

To convert a decimal into a percentage, first we have to convert it into fractional form.

Because percentages are out of 100, the resulting fraction would be 3/100.

Next, to find the decimal, we would just divide the fraction (numerator divided by denominator).

3 % = 3/100 = 0.03

8 0

3 years ago

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Given a situation involving a dilation, how do you determine the scale factor.

USPshnik [31]

Answer:

See explanation below.

Step-by-step explanation:

The scale factor can be found by dividing two corresponding side lengths. For instance, if you have two triangles, divide the new length of the larger or smaller triangle by the same side length of the original.

If the side length of the new was 9 and the old was 3 then the scale factor would be 9/3 = 3.

If it were flipped then the new would be 3 and the old would be 9. So the scale factor would be 3/9 = 1/3.

4 0

3 years ago

About 11% of people are left-handed. How e = 0.11• 30 e = 3.3 many people would you expect to be left-handed in a class about 3

Marizza181 [45]

Answer:

There are about 3 students that are left handed in a class. First Sara took the percentage of left handed people, 11%, and multiplied it by the amount of students in the class, 30. She got 3.3 but you can't have 0.3 of a person so she rounded it down to 3.

6 0

2 years ago

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