I need help quick!!!!! Ive been trying to figure this out for 20 mins now.

Polymer composite materials have gained popularity because they have high strength to weight ratios and are relatively easy and

Brums [2.3K]

Answer:

$t=\frac{51.6-48}{\frac{1.1}{\sqrt{10}}}=10.349$

$p_v =P(t_9>10.349)=1.34x10^{-6}$

If we compare the p value and the significance level given for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the the actual mean is significantly higher than 48 MPa at 5% of significance.

Step-by-step explanation:

1) Data given and notation

$\bar X=51.6$ represent the sample mean

$s=1.1$ represent the standard deviation for the sample

$n=10$ sample size

$\mu_o =48$ represent the value that we want to test

$\alpha=0.05$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the mean score is higher than 48, the system of hypothesis would be:

Null hypothesis: $\mu \geq 48$

Alternative hypothesis: $\mu > 48$

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

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

$t=\frac{51.6-48}{\frac{1.1}{\sqrt{10}}}=10.349$

Calculate the P-value

First we find the degrees of freedom:

$df=n-1=10-1=9$

Since is a one-side upper test the p value would be:

$p_v =P(t_9>10.349)=1.34x10^{-6}$

Conclusion

If we compare the p value and the significance level given for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the the actual mean is significantly higher than 48 MPa at 5% of significance.

5 0

3 years ago

On the first play during the football game our team gained 5 yards. Between both the second and third play our team lost eight y

Maurinko [17]

Answer:

loss

Step-by-step explanation:

you might want to check someone else answer first tho

7 0

3 years ago

Rewrite the decimal fraction as a decimal number.

Sergio039 [100]

Answer:

8.025

Step-by-step explanation:

If you count the zeros in 1000, it's three. Count three starting from the back of 25. Add 0 in front of 25 to make it a three digit number. You then put the decimal point with the whole number.

7 0

3 years ago

What is the solution 4x+1y ≤48 and 10 ≤y ?

PIT_PIT [208]

The answer is X=19/2 y=10

6 0

3 years ago

Please help with 1 & 2

yaroslaw [1]

First question:

I urge you to perform the division using the synthetic division method:

________________
-4 / 1 3 -6 -6 8
-4 4 8 -8
-----------------------
1 -1 -2 2 0

Note that there is no remainder. When this is the case, the divisor (here, that's -4) is a root of the given polynomial, and the value of that polynomial, g(-4), is 0.

If the remainder were not 0, then the remainder represents the value of the polynomial for that particular divisor. For example, if x = -3, the remainder is -28. We'd write that as g(-3) = -28.

But here, g(-4) = 0.

6 0

3 years ago