Question

8. A sample of observations on maximum concrete pressure (kN/m2) based on The article "Concrete Pressure on Formwork” (Mag. of Concrete Res., 2009: 407-417) is as follows: 33.2, 41.8, 37.3, 40.2, 36.7, 39.1 and 36.2 Does a confidence interval suggest that the standard deviation of maximum pressure exceeds 2.6 (kN/m2).

Answer 1

Ho:8=2.6 vis H. 6+2.6. le find 95.1. confidance interval for fi. = 6c Tenis2 I taky (0-1) 110-125² 7 X1-42 (:1) Hen seal(5x;? -(3x)2 ] nl \ ñ X: concrete pressure on framewort. Exo 264, 5 1 EX2 = 10042.95 .ine7 8.1048 0.995. S4= L ( 10042.95 - (2645)2 = 7-1 2=0.05, 4/2=0.025 1-2/2 = Xčnay Cel)) = X 20.025) = 14.45 A(n-1) (1-2/2) = Kec.COgas) = 1.24. | 5x8-1048_4 sx Pilouge ) 6 x 8.1048 14.45 6X 8'1048 1.24 Cla8345 6.2623. a lower bound=1.8345 Upper bound = 6-2623 2 The go.l. confidance ind includes value 2.6 we may acoept Hoi This mean side CS sdosa doricuximam pressure not exceeel 2:6:(KM1m? CamScanner