84. 63 : = 121 110

$$\frac{84}{121} : \frac{63}{110} = \frac{84}{121} \cdot \frac{110}{63} = \frac{84 \cdot 110}{121 \cdot 63} = \frac{12 \cdot 10}{11 \cdot 9} = \frac{4 \cdot 10}{11 \cdot 3} = \frac{40}{33} = 1\frac{7}{33}$$

Ответ: $$1\frac{7}{33}$$