An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 290 engines and the mean pressure was 7.6 pounds/square inch (psi). Assume the population standard deviation is 0.8. The engineer designed the valve such that it would produce a mean pressure of 7.5 psi. It is believed that the valve does not perform to the specifications. A level of significance of 0.02 will be used. Find the value of the test statistic. Round your answer to two decimal places.

z(s) =  - 2,15 We accept H₀

Step-by-step explanation:

Assume Normal Distribution.

Sample size                  n = 290

Sample mean               μ = 7,6

Sample standard deviation   s = 0,8

Level of significance  0,02   ( CI = 98 % )

population mean  μ₀ = 7,5

α = 0,02       the valve could fail under and above the spec value ( 7,6 ) therefore we must develop a two-tail test

α/2  =  0,01

Hypothesis Test

Null hypothesis                                      H₀       μ   =  μ₀

Alternative Hypothesis                         Hₐ        μ   ≠  μ₀

for  α  =  0,01    z(c)  = - 2,3

To calculate  z(s)

z(s)  =  ( μ   -  μ₀ ) / s/√n

z(s)  =  ( 7,5 - 7,6 ) /0,8/√290

z(s) = - 0,1 * 17 /0,8

z(s) =  - 1,7 / 0,8

z(s) =  - 2,15

Comparing   z(s)  and  z(c)

- 2, 15  < - 2,3

|z(s)|  <  | z(c)|

Then z(s) is in the acceptance region. We don´t have evidence to reject H₀

135 is your answer

step-by-step explanation:

try 180 times three then divide that number by 4 (sides) to get your answer. im glad to : )

6. 104

7. 52/37

8. 2704

9. 140608

10. -52

11. |52|=52

12. 1/52

13. 156

14. 26

15. 40

16. 37

17. -364

18. 53 1/3

19. 50.96

20. 43 2/3

21. 78

22. 50.75

23. 47.63

24. 163.28

25. 10400

26. 338

27. 208

28. 2704 square inches

29. 312 square meters

30. don't know what its asking, tell me so i can tell you

31. 8490.56

32. 52 degrees would be an acute angle

33. 128 degrees

34. 20.8

35. 39

36. 208