Question

4. The Ti content (wt%) of two different ore samples was measured several times by the same method. The results for sample 1 were <x> = 0.013960 and si = 0.0003435 for five measurements and the results for sample 2 were <x2> 0.013400 and s2 = 0.0003937 for four measurements. Are the two results significantly different at the 95th confidence level?

Answer 1

u from the student t test tuble, the value of tant the 15). confidence level += 2.78 (for 4 experiments) for expennent ! (x) = 0.013960 No ot expenment N = 4 s = 0.0003435 951 Confedence Lenost - ā tū 2-78 * 0.0003435 = 0.013960+ v4 . 0.013960 + 0.00047 for caperiment 2 Difference - 0.013960 +000047) -(0.013960 -0.00047 Difference - 9.4x10-4 <a) -0.013400 s'= 00003937 95% writidence Limit = 2.78 * 0.0003937 = 0.013400 I - 19 2-0.013400 1 0.00054 Difference = 1.08x10-3 So, Enpenment is more apt and perfect than that of the exponment 2 as the difference between the meanum and mineman value is less.