100%
caption
<math>\frac{5}{7} + \frac{3}{7} = \frac{5 + 3}{7} = \frac{8}{7} = 1\frac{1}{7}</math>
<math>\frac{5}{7} - \frac{3}{7} = \frac{5 -3}{7} = \frac{2}{7} </math>
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