Table I: Area under the Normal Density Function

To use the table, identify the value of $x$ for which you want to find $\mathrm{\Phi }(x)$ . The table is structured with $x$ values in increments of 0.1 along the rows and 0.01 along the columns. For example, to find $\mathrm{\Phi }(1.25)$ , locate the row for 1.2 and the column for 0.05. The intersection of this row and column provides the cumulative probability value, which represents $\mathrm{\Phi }(1.25)$ .

For negative values of $x$ , the table can still be used by leveraging the symmetry: $$\mathrm{\Phi }(-x)=1-\mathrm{\Phi }(x).$$