solve the following:
[tex]1. \frac{1}{4} + \frac{2}{4} = [/tex]

[tex]2. \frac{3}{7} + \frac{1}{2} = [/tex]

[tex]3.3 \frac{3}{5} - 1 \frac{1}{5} = [/tex]

[tex]4. \frac{7}{9} - \frac{1}{3} = [/tex]

[tex]6. \frac{2}{3} \div \frac{9}{11} = [/tex]
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