[tex] \frac{6}{7} - \frac{1}{4} [/tex]
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The lowest common multiple of 7&4 is 28 (7x4)
Convert both fractions to [tex] \frac{}{28} [/tex]
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[tex] \frac{6}{7}= \frac{24}{28} [/tex] (6x4=24 & 6x7=28)
[tex] \frac{1}{4} \frac{7}{28} [/tex]
[tex] \frac{24}{28} - \frac{7}{28}= \frac{17}{28} [/tex]
