Engineers' Investigation on Tire Life with New Rubber Compound

Engineers at a tire manufacturing company conducted an investigation to determine the effect of a new rubber compound on the tire life of a certain brand of tires. They took a sample of 16 tires and constructed a 99 percent confidence interval for the mean tire life, in miles. The interval they found was 62,550±2,026.

This means that based on the data collected, the engineers are 99 percent confident that the true mean tire life of the tires lies within the range of 62,550-2,026 to 62,550+2,026 miles. In other words, the engineers are very confident that the mean tire life falls between 60,524 miles and 64,576 miles.

Now, if the company intends to claim a maximum tire life for advertising purposes, the maximum plausible value for the mean tire life would be the upper limit of the confidence interval. In this case, the upper limit is 62,550 + 2,026 = 64,576 miles. Therefore, the maximum plausible value for the mean tire life, in miles, based on the engineers' 99 percent confidence interval is 64,500 miles.