Código mysql:
Ver original+----------+----------------+-----------+
| num_test | nom_persona | resultado |
+----------+----------------+-----------+
| 1 | maria | 6 |
| 2 | maria | 7 |
| 3 | maria | 9 |
| 2 | juan | 4 |
| 3 | juan | 8 |
| 1 | pedro | 7 |
| 2 | pedro | 2 |
| 3 | pedro | 1 |
| 1 | maria fernanda | 3 |
+----------+----------------+-----------+
Query OK, 0 rows affected (0.00 sec)
+----------+----------------+-----------+
| num_test | nom_persona | resultado |
+----------+----------------+-----------+
| 1 | maria | 6 |
| 2 | maria | 7 |
| 3 | maria | 9 |
| 1 | maria fernanda | 3 |
+----------+----------------+-----------+
mysql>
Un saludo.