Adding and Subtracting Larger Numbers

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Adding and Subtracting Larger Numbers Rules for Adding & Subtracting Integers 1 + & - becomes - (2+(-3)=2-3-4-(+8)=-4-8) 2 + & + becomes + (5+(+1)=5+1-7+(+3)=-7+3) 3 - & - becomes + (4-(-6)=4+6-9-(-2)=-9+2) Let’s look at some examples (1) Find (30) + (−23) + (− 63) + (+ 55) (30) + (−23) + (− 63) + (+ 55) = 30 − 23 − 63 + 55 = 30 + 55 − 23 − 63 Taking − common = (30 + 55) − (23 + 63) = 85 − 86 Taking − common = − (− 85 + 86) = − (86 − 85) = −1 Rough + & − becomes − + & + becomes + − & − becomes + (2) Find the sum of (–10), (92), (84) and (–15) (−10) + 92 + 84 + (−15) = −10 + 92 + 84 − 15 = 92 + 84 − 10 − 15 Taking − common = (92 + 84) − (10 + 15) = 176 − 25 = 151 Rough + & − becomes − + & + becomes + − & − becomes + (3) 5 + (+1) = 5 = 6 (4) −7 + (+3) = −7 Taking − common = −(7 − 3) = − 4 (5) 4 − (−6) = 4 = 10 Rough + & − becomes − + & + becomes + − & − becomes + (6) −9 − (−2) = −9 Taking − common = −(9 − 2) = −7 Rough + & − becomes − + & + becomes + − & − becomes +