Add 58 base eight and 67base eight giving the answer in base eight

To add 58 base eight and 67 base eight, we first convert each number to base ten.

58 base eight = 5*(8^1) + 8^0 = 5*8 + 1 = 41 base ten
67 base eight = 6*(8^1) + 7*(8^0) = 6*8 + 7 = 55 base ten

Next, we add the base ten numbers:
41 + 55 = 96

Lastly, we convert the sum, 96 base ten, back to base eight.
To do this, we divide 96 by 8 until we reach a quotient of 0.
96 ÷ 8 = 12 with a remainder of 0,
12 ÷ 8 = 1 with a remainder of 4,
1 ÷ 8 = 0 with a remainder of 1.

Reading the remainders backward, we get 140 base eight.

Therefore, 58 base eight + 67 base eight = 140 base eight.

58 is not a valid base-8 number.

Only the digits 0-7 may be used.

Apologies for the mistake. Let's correct it.

To add 58 base eight and 67 base eight, we convert each number to base ten.

58 base eight = 5*(8^1) + 8^0 = 5*8 + 8 = 40 base ten
67 base eight = 6*(8^1) + 7*(8^0) = 6*8 + 7 = 55 base ten

Next, we add the base ten numbers:
40 + 55 = 95

Lastly, we need to convert the sum, 95 base ten, back to base eight.
Dividing 95 by 8 until we reach a quotient of 0:
95 ÷ 8 = 11 with a remainder of 7,
11 ÷ 8 = 1 with a remainder of 3,
1 ÷ 8 = 0 with a remainder of 1.

Reading the remainders backward, we get 137 base eight.

Therefore, 58 base eight + 67 base eight = 137 base eight.