Convert \( (42_5) \) to base three: First, convert to decimal: \(42_5 = 4 \times 5 + 2 = 22_{10}\) Now convert \( (22_{10}) \) to base three: 22 \(\div 3 = 7 \quad ; \, r1 \) 7 \(\div 3 = 2 \quad ; \, r1 \) 2 \(\div 3 = 0 \quad ; \, r2\) Read the remainders from bottom to top: \(22_{10} = 211_3\).