In Problems 23–32, assume that the random variable X is normally distributed, with mean μ = 50 and standard deviation σ = 7. Compute the following probabilities. Be sure to draw a normal curve with the area corresponding to the probability shaded.
P(40 < X < 68)
Step 1 of 5) Compute the following probabilities. Be sure to draw a normal curve with the area corresponding to the probability shaded. P(40 < X < 68). The process ends when any remaining explanatory variables not in the model have P-values greater than the level of significance when added to the model. The backward elimination method also works in steps. The process begins with all the explanatory variables in the model. At each step one explanatory variable is eliminated from the model. For an explanatory variable to be eliminated, it must have the largest P-value that is greater than the specified level of significance. The process ends when any explanatory variables that remain in the model have P-values less than the level of significance. Next, we present the steps utilized for stepwise regression. Stepwise Regression Procedure 1. Find a simple linear regression equation for each of the explanatory variables.