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so above this dotted line I have a certain number of boxes and we could see each of these gold bars they have ten boxes in a one two three four five six seven eight nine ten and I have two groups of these tens so I have two tens I have two tens and I have one two three ones that's how many boxes I have above that line and below that line I have one two three four tens four tens and I have one two three four five I have five ones so this first number is two tens and three ones or 23 two tens three ones the second number is four tens and five ones four tens and five ones 45 now what I want to do is add the numbers so let's do that let's add so let's add that amount this amount to this amount twenty-three to forty-five well I have three ones here I have five ones here so if you add those two those you're going to end up with eight ones so let me do that in that blue color so you're going to have one two three four five six seven eight and if we look at over if we look at it over here where we write down the numbers with with digits or the numerals then here you're going to have three ones plus 5 ones is eight ones eight ones eight ones now you have two tens plus four tens well that's going to be six tens so let me actually copy and paste this so I have two tens so 2 plus 4 is 6 so 2 4 + 2 4 and 6 so I have I have let me change my tool so I have 1 2 3 4 5 6 tens whoops using the wrong thing I have I have six tens so just like that you can see when I add 23 to 45 I just added the ones place three plus five was eight three plus five is eight three ones plus 5 ones is eight ones and I ended the tens place two tens plus four tens is equal to six tens so I got 68