From the given statement:
[tex]\begin{gathered} \text{Fraction of Mrs Frank's class that likes oatmeal = }\frac{2}{3} \\ \text{Fraction of Mrs Donaldson's class that likes oatmeal = }\frac{1}{4} \end{gathered}[/tex]To determine the fraction amount of the classes that like oatmeal, we add the fraction that likes oatmeal from each class.
[tex]i\text{.e }\frac{2}{3}+\frac{1}{4}[/tex]To add the fraction, the first step is to find the lowest common multiple (L.C.M) of the denominators.
L.C.M of 3 and 4 is 12
Therefore:
[tex]\begin{gathered} \text{ }\frac{2}{3}+\frac{1}{4}=\frac{2\times4+1\times3}{12} \\ =\frac{8+3}{12} \\ =\frac{11}{12} \end{gathered}[/tex]We can then say that the fraction amount of the classes that like oatmeal is 11/12.
