Answer: 1. 165₁₀ - 165 ÷ 8 = 20 with a remainder of 5- 20 ÷ 8 = 2 with a remainder of 4- 2 ÷ 8 = 0 with a remainder of 2- Reading the remainders in reverse order: 245₈2. 251₁₀ - 251 ÷ 8 = 31 with a remainder of 3- 31 ÷ 8 = 3 with a remainder of 7- 3 ÷ 8 = 0 with a remainder of 3- Reading the remainders in reverse order: 373₈3. 398₁₀ - 398 ÷ 8 = 49 with a remainder of 6- 49 ÷ 8 = 6 with a remainder of 1- 6 ÷ 8 = 0 with a remainder of 6- Reading the remainders in reverse order: 616₈4. 99₁₀ - 99 ÷ 8 = 12 with a remainder of 3- 12 ÷ 8 = 1 with a remainder of 4- 1 ÷ 8 = 0 with a remainder of 1- Reading the remainders in reverse order: 143₈5. 87₁₀ - 87 ÷ 8 = 10 with a remainder of 7- 10 ÷ 8 = 1 with a remainder of 2- 1 ÷ 8 = 0 with a remainder of 1- Reading the remainders in reverse order: 127₈ The octal equivalents of the given decimal numbers are: 1. 165₁₀ = 245₈2. 251₁₀ = 373₈3. 398₁₀ = 616₈4. 99₁₀ = 143₈5. 87₁₀ = 127₈ follow me for more! :)