Final Answer:
1) $\frac{20}{2} \cdot \frac{4}{5} \cdot \frac{3}{8} = \frac{\cancel{20}^4}{\cancel{2}^1} \cdot \frac{\cancel{4}^1}{\cancel{5}^1} \cdot \frac{3}{\cancel{8}^2} = \frac{4 \cdot 1 \cdot 3}{1 \cdot 1 \cdot 2} = \frac{12}{2} = 6$
2) $\frac{4}{9} \cdot \frac{6}{7} = \frac{4 \cdot \cancel{6}^2}{\cancel{9}^3 \cdot 7} = \frac{4 \cdot 2}{3 \cdot 7} = \frac{8}{21}$
3) $\frac{15}{7} \cdot \frac{21}{16} = \frac{\cancel{15}^15}{\cancel{7}^1} \cdot \frac{\cancel{21}^3}{16} = \frac{15 \cdot 3}{16} = \frac{45}{16}$
4) $\frac{30}{3} \cdot \frac{15}{7} = \frac{\cancel{30}^{10}}{\cancel{3}^1} \cdot \frac{15}{7} = \frac{10 \cdot 15}{7} = \frac{150}{7}$
5) $\frac{14}{15} \cdot \frac{5}{7} = \frac{14 \cdot \cancel{5}^1}{\cancel{15}^3 \cdot 7} = \frac{14}{3 \cdot 7} = \frac{14}{21} = \frac{2}{3}$
6) $\frac{3}{20} \cdot \frac{10}{24} = \frac{\cancel{3}^1}{\cancel{20}^2} \cdot \frac{\cancel{10}^1}{\cancel{24}^8} = \frac{1 \cdot 1}{2 \cdot 8} = \frac{1}{16}$
7) $\frac{24}{2} \cdot \frac{5}{12} = \frac{\cancel{24}^{12}}{\cancel{2}^1} \cdot \frac{5}{\cancel{12}^1} = \frac{12 \cdot 5}{1 \cdot 1} = 60$
8) $\frac{12}{15} \cdot \frac{21}{8} = \frac{\cancel{12}^4}{\cancel{15}^5} \cdot \frac{21}{8} = \frac{4 \cdot 21}{5 \cdot 8} = \frac{84}{40} = \frac{21}{10}$
9) $\frac{25}{6} \cdot \frac{81}{20} = \frac{\cancel{25}^5}{\cancel{6}^2} \cdot \frac{81}{\cancel{20}^4} = \frac{5 \cdot 81}{2 \cdot 4} = \frac{405}{8}$
10) $\frac{12}{5} \cdot \frac{20}{2} = \frac{12}{\cancel{5}^1} \cdot \frac{\cancel{20}^4}{\cancel{2}^1} = 12 \cdot 4 = 48$
Parent Tip: Review the logic above to help your child master the concept of cross multiplication worksheet.
