Find a common denominator for \(\frac{1}{3}\) and \(\frac{1}{12}\) by dividing each whole into the same number of equal parts. Use the models to help.

common denominator:

\(\frac{1}{2}\) and \(\frac{1}{4}\)

\(\frac{3}{4}\) and \(\frac{5}{8}\)

\(\frac{1}{3}\) and \(\frac{1}{4}\)

\(\frac{4}{12}\) and \(\frac{5}{8}\)

\(\frac{1}{4}\) and \(\frac{5}{6}\)

\(\frac{3}{5}\) and \(\frac{4}{10}\)

Jerry has two same-size circles divided into the same number of equal parts. One circle has \(\frac{3}{4}\) of the parts shaded, and the other has \(\frac{2}{3}\) of the parts shaded.  His sister says the least number of pieces each circle could be divided into is 7. Is his sister correct? Explain.