A researcher believes that female stray cats are more cautious when approaching people than male cats. He knows that the stray cat population is 50% male and 50% female. In order to test this, visits 15 different areas where stray cats live and records the gender of the first cat to approach him. He finds that 12 of the 15 cats that approach him are male. Using a sign test: c) What is the obtained value (number of female cats firstly approached to the researcher )?