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MENTAL MATH PART III. SUBTRACTION & THE LAST OF HWK #1. SUBTRACTION -TRADING ONE PROBLEM FOR ANOTHER. If you would like to change A-B to an easier problem then you should do what to the numbers to assure that you get the same answers?
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MENTAL MATH PART III SUBTRACTION & THE LAST OF HWK #1
SUBTRACTION -TRADING ONE PROBLEM FOR ANOTHER If you would like to change A-B to an easier problem then you should do what to the numbers to assure that you get the same answers? Add or subtract the same number to both. Make the number you subtract as easy as possible to work with!
EXAMPLES • 198-89 =209-100=109 • 1533-367 = 1566-400=1166 • 121-88 =123-90 =133-100=33
One More Example 2021-857 =2024-860 =2064-900 =2164-1000 =1164
Compensating one digit at a time 3091 -867 ------------ 2 2 2 4 7 to 10 is 3 3+1 =4 But the 9 is now an 8. 8-6 is 2 8 to 10 is 2 0+2 is 2 But the 3 is now a 2.
Compensating one digit at a time 5 4 3 2 1
Compensating one digit at a time 0 0 0 0 0 0 0 0 0
Each letter is a different digit – find them! If you get stuck just text me at 7757220658 For a hint!