tlng ksh tau please... poin nya besar nih

3. 18/21 × 15/20 = 270/420 ×25/30 = 6,750/12,600

4. 5 4/5 × 4 2/3 = 29/5 × 14/3 = 406/15

[tex] \frac{18}{21} \times \frac{15}{20} \times \frac{25}{30} = \frac{6}{7} \times \frac{1}{4} \times \frac{5}{2} = \frac{3}{7} \times \frac{1}{4} \times 5 = \frac{15}{28} [/tex]

[tex]5 \frac{4}{5} \times 4 \frac{2}{3} = 4 \times 4 \times \frac{2}{3} = \frac{32}{3} = 10 \frac{2}{3} [/tex]