Example 

Find the Highest Common Factor of 54, 72 and 150.

First we consider 54 and 72. The HCF for these two quantities is calculated as follows:

                                    54) 72 (1
                                          54
                                      ---------
                                     18) 54 (3
                                          54
                                      -------
                                          0
                                     -------

The HCF is 18. Now we consider 18 and 150 and obtain the HCF for these two quantities. It will be obtained as follows.

                                    18) 150 (8
                                          144
                                       ---------
                                     6) 18 (3
                                         18
                                      -------
                                          0
                                      -------

We observe that 6 is the highest common factor for these two quantities. That is, 6 is the HCF of the three given quantities.