Answer:
Base 6 was used
Explanation:
Here, we want to find which number base was used for the addition calculation
We start by adding the two end numbers
4 + 5 = 9
But 3 was recorded;
That means we can have 6 as the number base( 9/6 = 1 r 3)
We still continue to verify this;
The next addition is 2+3 = 5, adding the 1 brought forward, we have 6, but 0 was recorded
6/6 is (1 r 0)
This still further corroborated the earlier assertion;
then lastly 3 + 1 + 1 (1 brought forward); 5
This was recorded directly to show that the base in question is not less than 5
Hence our base of addition is base 6