c) $\frac{1}{6}$ + $\frac{3}{4}$
= $\frac{4}{24}$ + $\frac{18}{24}$
= $\frac{21}{24}$
d) $\frac{9}{4}$ + 5
= $\frac{9}{4}$ +$\frac{5}{1}$
= $\frac{9}{4}$ + $\frac{20}{4}$
= $\frac{29}{4}$
e) $\frac{4}{24}$ + $\frac{1}{4}$
= $\frac{4}{24}$ + $\frac{6}{24}$
= $\frac{10}{24}$
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