The sample average unrestrained compressive strength for 50 specimens of a particular type of brick was computed to be 3120 psi, and the sample standard deviation was 180. The distribution of unrestrained compressive strength may be somewhat skewed. We want to determine whether the data indicate that the true average unrestrained compressive strength is less than the design value of 3200. Test using α = 0.01.

The p-value of the test is 0.0014 < 0.01, meaning that the data indicates that the true average unrestrained compressive strength is less than the design value of 3200.

Step-by-step explanation:

We want to determine whether the data indicate that the true average unrestrained compressive strength is less than the design value of 3200.

At the null hypothesis, we test if the mean is at the design value of 3200, so:

At the alternate hypothesis, we test if it is less than the design value of 3200, so:

The test statistic is:

In which X is the sample mean, is the value tested at the null hypothesis, s is the standard deviation of the sample and n is the size of the sample.

3200 is tested at the null hypothesis:

This means that

The sample average unrestrained compressive strength for 50 specimens of a particular type of brick was computed to be 3120 psi, and the sample standard deviation was 180.

This means that

Test statistic:

P-value of the test and decision:

The p-value of the test is the probability of finding a sample mean below 3120, which is the p-value of t = -3.14, using a one-tailed test, with 50 - 1 = 49 degrees of freedom.

With the help of a calculator, the p-value of the test is 0.0014

The p-value of the test is 0.0014 < 0.01, meaning that the data indicates that the true average unrestrained compressive strength is less than the design value of 3200.

part 1 answer = 8

part 2 answer = 72

step-by-step explanation:

part 1 explanation = add all of the numbers, then divide by how many numbers you have. so, 200/25 = 8.

part 2 explanation = not gonna lie, this is hard to explain, so just google how to do it.

9) i can't see the angle so whatever it is just do this: cos(angle) x hypotenuse and then use that answer and they hypotenuse and plug it into this: (answer you just got)^2 + b^2 = (hypotenuse)^2. the first answer will be the answer of the adjacent side and the second answer after this equation will be the opposite side.

10) y = 14 x = √147 or 12.12435565

11) x = 4.8

12) x = 4.2

13) x = 9.3

14) pq: 13.2

qr : 17.6

angle p: 53º

15) angle c: 54.3º

angle a: 35.7º

16) h = 21040

v = 1841

step-by-step explanation:

10) 7/sin(30) = 14 = y

7^2 + b^2 = 14^2

49 + b^2 = 196

b^2 = 196 - 49

√b^2 = √147

x = √147

11) cos(70) x 14 = 4.788282007

x = 4.8

12) tan(25) x 9 = 4.196768923

x = 4.2

13) sin(31) x 18 = 9.270685348

x = 9.3

14) pq: sin(37) x 22 = 13.23993051

pq: 13.2

qr: cos(37) x 22 = 17.56998122

qr : 17.6

angle p: 180 - (37 + 90) = 53º

15) cos-1(7/12) = 54.31466529

angle c: 54.3º

angle a: 180 - (90 + 54.31466529) = 35.68533471

angle a: 35.7º

16) 4 x 5280 = 21120

cos(5) x 21120

h = 21039.63202

h = 21040

sin(5) x 21120

v = 1840.729287

v = 1841