The least common multiple of the three denominators is 16 because:
[tex] 4 \times 4 = 16 \\ 16 \times 1 = 16 \\ 8 \times 2 = 16 [/tex]
Change the fractions so that each fraction has a denominator of 16.
[tex] \frac{3 \times 4}{4 \times 4} = \frac{12}{16} [/tex]
[tex] \frac{7 \times 1}{16 \times 1} = \frac{7}{16} [/tex]
[tex] \frac{5 \times 2}{8 \times 2} = \frac{10}{16} [/tex]
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[tex] 1. \frac{12}{16} \\ \\ 2. \frac{7}{16} \\ \\ 3. \frac{10}{16} [/tex]