Based on data collected from its production processes, Crosstiles Inc.determines that the breaking strength of its most popular porcelain tile is normally distributed with a mean of
400 pounds per square inch and a standard deviation of 12.5 pounds per square inch.Based
On the 68-95-99.7 Rule, about what percent of its popular porcelain tile will have breaking
Strengths greater than 412.5 pounds per square inch?
A)95%
B)68%
C)16%
D)32%

Question

Quizplus · Accepted Answer

According to the 68-95-99.7 Rule (or the Empirical Rule), approximately 68% of data within a normal distribution falls within one standard deviation of the mean. Since 412.5 pounds per square inch is one standard deviation above the mean (400 + 12.5), about 34% of the tiles will have breaking strengths between 400 and 412.5 pounds per square inch, and another 34% will be between 400 and 387.5 pounds per square inch. Therefore, about 16% (100% - 84%) will have breaking strengths greater than 412.5 pounds per square inch.

Based on Data Collected from Its Production Processes, Crosstiles Inc