1 per 6 ditambah 1 per 9 = pakai cara

[tex] = \frac{1}{6} + \frac{1}{9} [/tex]
Cari penyebut baru (6*9)= 54

[tex] = \frac{54 \div 6}{54} + \frac{54 \div 9}{54} \\ = \frac{9 + 6}{54} \\ = \frac{15}{54} [/tex]

1/6+1/9=9/54+6/54=15/54