The average number of surviving bacteria in a canned food product () were recorded for various lengths ( x, in minutes) of exposures to a temperature of 300° . Suppose a natural log transformation for the response variable was required. The least - squares estimate of the regression line was hat(){()|x) = 5.339 - 0.236x . In addition, a 95% confidence interval for the slope of the regression line was from -0.259 to -0.214 . Moreover, a 95% prediction interval for the natural o of the number of surviving bacteria with 5 minutes of exposure to 300° was from 3.877 to 4.439 .
Interpret the estimate of the slope of the regression line, -0.236 , on the original scale.