base eight: 4 flats, 0 longs, 5 units

In base eight, 4 flats, 0 longs, and 5 units can be represented as 405.

To convert the base-eight number 405 into base-ten, you need to calculate the decimal equivalent of the number:

Step 1: Write down the given base-eight number: 405.

Step 2: Identify the place values of each digit in the base-eight number. The rightmost digit is in the units place, the second digit is in the longs place, and the leftmost digit is in the flats place.

Step 3: Convert each digit to its base-ten equivalent. In base eight, the digit 5 is equivalent to 5 in base ten, the digit 0 is equivalent to 0 in base ten, and the digit 4 is equivalent to 4 in base ten.

Step 4: Multiply each digit by its respective place value. Starting from the right, multiply 5 (units place) by 8^0 to get 5, multiply 0 (longs place) by 8^1 (8) to get 0, and multiply 4 (flats place) by 8^2 (64) to get 256.

Step 5: Add up the results from step 4. 5 + 0 + 256 equals 261.

Therefore, the base-eight number 405 is equivalent to 261 in base ten.