What is the result of 3 gross 2 dozen 4 ones minus 7 dozen 6 ones?

Answer 1

Hi, I had a problem with this very same question. Here is the answer: 2 Gross 6 Dozen 10 Ones To get this answer, you must subtract using 12s instead of 10s as you would normally do with regular subtraction and involving the rules of "borrowing". You are essentially using The Base-Twelve or Duodecimal System to solve this problem. It is easier than it sounds but you might have to read this a few times to fully understand it without having a picture drawn out for you. First you set up this problem as a vertical subtraction problem lining up the grosses, dozens and ones. Then start with the furthest right hand column as you would normally do in a subtraction problem. You can not subtract 6 ones from 4 ones so you must borrow from the dozens column as you would if trying to subtract 6 from 1 in a typical subtraction problem, typically you would scratch of the number you are borrowing from and then add 10 to the number you are subtracting from..HOWEVER IN THIS PROBLEM THE ONLY THING YOU DO DIFFERENTLY IS ADD 12 TO THE NUMBER BEING SUBTRACTED FROM. You scratch off 2 dozen and place a 1 in that column and then you scratch off the 4 in the ones column and add the "twelve" you borrowed from the left column making it 4 plus 12 which equals 16. Now 16 ones minus 6 ones=10 ones. Place 10 ones under the subtraction bar. You are done with the ones column and now move to the next column being dozens. Now you move to the dozen column. You cannot subtract 7 dozen from 1 (remember, we borrowed from this so it is no longer a 2 but now a 1) dozen unless you borrow from the left column (gross). As you did before, follow the same steps. Put a line through 3 gross and put a 2 above it. Now put a line through 1 dozen and add the borrowed 12 to the 1 giving you a total of 13 dozen to subtract the 7 dozen from which equals 6 dozen. Again, place this answer under the subtraction bar and your dozens column is done. Now move to the gross column. The gross column is no longer 3 but now 2 because you borrowed1 from it to give you "12" more in the dozens column. Therefore 2 gross minus 0 gross gives you 2 gross and the grand total being: 2 GROSS 6 DOZEN 10 ONES