Perkalian Pecahan
Cara perkalian pecahan, pembilang dikali pembilang, penyebut dikali penyebut.
Contoh:
- \(\dfrac{2}{3}\times \dfrac{3}{4} = \dfrac{2\times 3}{3\times 4} = \dfrac{6}{12} = \dfrac{1}{2}\)
- \(\dfrac{4}{7}\times \dfrac{2}{5} = \dfrac{4\times 2}{7\times 5} = \dfrac{8}{35}\)
- \(\dfrac{5}{9}\times \dfrac{1}{8} = \dfrac{5\times 1}{9\times 8} = \dfrac{5}{72}\)
Pembagian Pecahan
Bentuk pembagian pecahan,
\(\dfrac{a}{b} \div \dfrac{c}{d}, \text{ dengan } b,d \neq 0\)
dapat kita ubah menjadi bentuk perkalian pecahan:
\(\bbox[yellow, 5pt]{\dfrac{a}{b} \div \dfrac{c}{d} = \dfrac{a}{b} \times \dfrac{d}{c} = \dfrac{a\times d}{b\times c}}\)
Contoh:
- \(\dfrac{3}{11}\div \dfrac{2}{5} = \dfrac{3}{11}\times \dfrac{5}{2} = \dfrac{3\times 5}{11\times 2} = \dfrac{15}{22}\)
- \(\dfrac{4}{5}\div \dfrac{3}{10} = \dfrac{4}{\cancel{5}}\times \dfrac{\cancelto{2}{10}}{3} = \dfrac{8}{3}\)
- \(\dfrac{5}{7}\div \dfrac{1}{35} = \dfrac{5}{\cancel{7}}\times \dfrac{\cancelto{5}{35}}{1} = 25\)