Числовое выражение:
\[\left(\frac{(1\frac12)^3-1\frac34}{4\frac78}\right)-\left(\frac{2\frac23}{10\frac12}\cdot1\frac5{16}\right).\]
\((1\frac12)^3=(\frac32)^3=\frac{27}{8}\), \(\frac{27}{8}-\frac74=\frac{13}{8}\), \(\frac{13}{8}:\frac{39}{8}=\frac13\).
\(2\frac23:10\frac12=\frac83:\frac{21}{2}=\frac{16}{63}\), \(\frac{16}{63}\cdot\frac{21}{16}=\frac13\).
\[\frac13-\frac13=0.\]
Ответ: 0.