Add the fractions $$ \dfrac{3}{8} $$ and $$ 6\dfrac{3}{4}$$.
We have: $$ 6 \dfrac {3}{4} = \dfrac {( 6 \times 4) +3 }{4} = \dfrac { 24 +3}{4} = \dfrac {27}{4} $$
$$LCM$$ of $$8$$ and $$4=8$$
$$ \therefore\dfrac38+\dfrac{27}8\\=\dfrac38\times \dfrac11+\dfrac{27}4\times\dfrac22\\= \dfrac 38+\dfrac{54}8\\=\dfrac{3+54}{8}\\ = \dfrac { 57}{8} = 7 \dfrac {1}{8} $$