Confidence interval for tungsten content of mined mineral

Reference no: EM13134066

Samples of ores from the face of a drift on twenty consecutive days and assayed for tungsten (W). The twenty assays average 1.50% W, with a variance of 0.1% W2. Calculate a 90% confidence interval for the tungsten content of the mined mineral. Further mining of the drift would be justified if the grade is above 1.25% W; can we be 95% confident that this is the case?

Reference no: EM13134066

Questions Cloud

Isosceles triangle and volume of prism : If I have a right prism with the prism height being 8 and the prism base being an isosceles triangle with a base of 3 (sides of 6) what is the lateral area and the volume of the prism

Accountant for ps group ltd : You are working as an accountant for PS Group Ltd. Your directors have asked you to prepare the necessary consolidation journal entries (20 marks) and a report (20 marks) answering the following question about consolidation procedures.

Solving for geometry word problems : A certain wheel has a diameter of 98 inches. If that wheel travels for 108 revolutions, then. How many years has it gone? (use 22/7 for pi)

Record of a deferred tax expense : The enacted tax rate increased to 30 percent in Year 2 compared to an enacted rate of 20 percent in the prior year. At December 31, Year 2, the company would record a deferred tax expense of ?

Confidence interval for tungsten content of mined mineral : Tungsten content of the mined mineral. Further mining of the drift would be justified if the grade is above 1.25% W; can we be 95% confident that this is the case?

How many grams of are cah2 needed : How many grams of are CaH2 needed to generate 147L of H2 gas if the pressure of H2 is 827 torr at 20 C?

Provision for imposition of civil liability : From the auditors point of view which of the following is a preferable provision for imposition of civil liability for financial damages?

Find statistical significance and practical significance : What is the difference between statistical significance and practical significance? Can a hypothesis test result be statistically significant and yet practically useless.

Calculate the concentration of ammonium ions : A solution is prepared by dissolving 19.9 g ammonium sulfate in enough water to make 100.0 mL of stock solution. A 15.00 mL sample of this stock solution is added to 59.00 mL of water.

User Account

All Pages