uji hipotesis distribusi normal, interval estimation

 

a.       n = 50 , xrata = 750,  s = 35

level kepercayaan 95% maka alpha=5%,  Z_0,025 =1,96

maka selangnya

xrata - Z_{0,025 .} s/  < u < xrata + Z_{0,025 .} s/

750 – 1,96.( 35 /  ) < u < 750 + 1,96.( 35 /  )

740,30 < u < 759,70  gram/hari

 

b.       s=30, alpha=10% , Z_0,05 = 1,65 , E = 5

maka banyak sampel

n = Z_{0,05 .}s² / E² = 1,65² . 30² / 5² = 98,01 = 98 sampel