Problem 4 21. In an attempt to compare the durability of two different materials (X and Y), 10. pleces of type X and 14 pieces of type Y were used. From these samples we calculate the statistics: X =...

Extracted text: Problem 4 21. In an attempt to compare the durability of two different materials (X and Y), 10. pleces of type X and 14 pieces of type Y were used. From these samples we calculate the statistics: X = 129.44, y =122.65, sx = 9.15, sy = 11.02. The pooled estimate of the standard devlation, sp., in the two-sample test statistic is: 106.01 10.28 105 72 10.30