5405 Octal in Decimal

Let's convert the octal number 5405 to decimal without using a calculator:

Write down the powers of 8 starting from the right, with the first digit corresponding to 8⁰, the second to 8¹, the third to 8², and so on.

Convert each octal digit to its decimal equivalent:

58 = 510

48 = 410

08 = 010

58 = 510

Multiply each octal digit by its corresponding power of 8 and sum the results.

(5 × 512) + (4 × 64) + (0 × 8) + (5 × 1) = 2560 + 256 + 0 + 5 = 2821