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\(\frac{{15}}{{11}} - \frac{8}{{11}} = \frac{7}{{11}}\)

\(\frac{{24}}{{19}} - \frac{{13}}{{19}} = \frac{{11}}{{19}}\)

\(\frac{{31}}{{21}} - \frac{{17}}{{21}} = \frac{{14}}{{21}}\)

\(\frac{{29}}{{35}} - \frac{{18}}{{35}} = \frac{{12}}{{35}}\)