[tex]1 \frac{1}{3} \times 2 \frac{1}{4} = \frac{4}{3} \times \frac{9}{4} = 3[/tex]
[tex] \frac{225}{100} \times 5 \frac{1}{10} = \frac{225}{100} \times \frac{51}{10} = \frac{459}{40} [/tex]
[tex]1 \frac{6}{9} \times \frac{9}{15} = \frac{15}{9} \times \frac{9}{15} = 1[/tex]