Question

neethu bought two peices of ribbon 5 1/6 m and 3 3/4 m . if she used 6 7/8 m from the whole , find the length of ribbon left with her

Answer 1

$5 \frac{1}{6} \: = \: \frac{31}{6} \: \: \: \: \: \: \: \: \: 3 \frac{3}{4} \: = \: \frac{15}{4} \: \: \: \: \: \: \: \: \: \: \: \: \: 6 \frac{7}{8} \: = \: \frac{55}{8} \\ \\ \: total \: length \: of \: ribbon \: neethu \: bought \: = \: \frac{31}{6} \: + \: \frac{15}{4} \\ \\ LCM\:of\:6\:and\:4\:=\:12 \\ \\ \frac{31 \times 2 + 15 \times 3}{12} \\ \\ \frac{62 + 45}{12} \\ \\ \frac{107}{12} \: \: \: metre \: of \: ribbon \: was \: bought \: by \: neethu. \\ \\ \\ \therefore \: \frac{107}{12} \: - \: \frac{55}{8} \: = \: length \: of \: ribbon \:left. \\ \\ LCM\:of\:12\:and\:8\:=\:48 \\ \\ \frac{107 \times 4 + 8 \times 6}{48} \\ \\ \frac{428 + 48}{48} \\ \\ = 429 \: metres \: of \: ribbon \:was \: left \: with \: neethu.$