Let's first simplify the given fractions: 3/12 and 75/100
We get,
[tex]\frac{3}{12}\text{ = }\frac{1}{4}\text{ and }\frac{75}{100}\text{ = }\frac{3}{4}[/tex]Let's now determine the fraction that is greater than 3/12 = 1/4, is less than 75/100 = 3/4, and has 6 as a denominator. We can try to presume that the missing fraction could be the in the middle of 1/4 and 3/4.
Let's find the fraction between 1/4 and 3/4:
[tex]\frac{\frac{1}{4}+\text{ }\frac{3}{4}}{2}\text{ = }\frac{1}{2}[/tex]Transforming 1/2 into a fraction of 6 denominator will be:
[tex]\frac{1}{2}\text{ = }\frac{1\text{ x 3}}{6}\text{ = }\frac{3}{6}[/tex]Therefore, we can say that 3/6 is the fraction that is greater than 3/12, is less than 75/100, and has 6 as a denominator.