n=60×(30×50/1000)1/2=60×1.22=73.2≈74(個(gè))答:份樣數(shù)是74個(gè)
n=20×(40×80/500)1/2=20×2.53=50.6≈51(個(gè))答:份樣數(shù)是51個(gè)