For a continuous series the mode is computed by the formula
1
\(l + \frac{{{f_{m - 1}}}}{{{f_m} - {f_{m - 1}} - {f_{m + 1}}}} \times C\;or\;l + \left( {\frac{{{f_1}}}{{{f_m} - {f_1} - {f_2}}}} \right) \times i\)
2
\(l + \frac{{{f_m} - {f_{m - 1}}}}{{2{f_m} - {f_{m - 1}} - {f_{m + 1}}}} \times C\;or\;l + \left( {\frac{{{f_m} - {f_1}}}{{{f_m} - {f_1} - {f_2}}}} \right) \times i\)
3
\(l + \frac{{{f_m} - {f_{m - 1}}}}{{2{f_m} - {f_{m - 1}} - {f_{m + 1}}}} \times C\;or\;l + \left( {\frac{{{f_m} - {f_1}}}{{2{f_m} - {f_1} - {f_2}}}} \right) \times i\)
4
\(l + \frac{{2{f_m} - {f_{m - 1}}}}{{{f_m} - {f_{m - 1}} - {f_{m + 1}}}} \times C\;or\;l + \left( {\frac{{2{f_m} - {f_1}}}{{{f_m} - {f_1} - {f_2}}}} \right) \times i\)