Addition and Subtraction Worksheet for Mental Math
Addition and Subtraction Worksheet for Mental Math
First, look at each table below. Then, follow Method 1 and Method 2 across each row. Finally, check that both methods reach the same answer — this way, this Addition and Subtraction Worksheet complete guide for Mental Math shows two solid paths to every solution, for every grade.
Grade 1 Addition and Subtraction Worksheet for Mental Math
First, Method 1 counts on or back one step at a time. Meanwhile, Method 2 uses a known doubles or near-doubles fact instead.
| No. | Problem | Method 1: Count On/Back | Method 2: Doubles Fact | Answer |
|---|---|---|---|---|
| 1 | 3 + 2 | Count on from 3: 3, 4, 5 | Think of 2+2=4 (a double), then add 1 more: 4+1 | 5 |
| 2 | 4 + 3 | Count on from 4: 4, 5, 6, 7 | Think of 3+3=6 (a double), then add 1 more: 6+1 | 7 |
| 3 | 6 − 2 | Count back from 6: 6, 5, 4 | Think of 6−1=5, then subtract 1 more: 5−1 | 4 |
| 4 | 5 + 2 | Count on from 5: 5, 6, 7 | Think of 2+2=4 (a double), then add 1 more: 4+1 | 7 |
| 5 | 8 − 3 | Count back from 8: 8, 7, 6, 5 | Think of 8−2=6, then subtract 1 more: 6−1 | 5 |
| 6 | 4 + 4 | Count on from 4: 4, 5, 6, 7, 8 | This is already a double: 4+4 | 8 |
| 7 | 9 − 4 | Count back from 9: 9, 8, 7, 6, 5 | Think of 9−5=4, then add 1 more: 4+1 | 5 |
| 8 | 6 + 3 | Count on from 6: 6, 7, 8, 9 | Think of 3+3=6 (a double), then add 3 more: 6+3 | 9 |
Grade 2 Addition and Subtraction Worksheet for Mental Math
Next, Method 1 breaks each number into tens and ones. Meanwhile, Method 2 uses number line jumps, which is easier because it needs no rounding at all.
| No. | Problem | Method 1: Tens and Ones | Method 2: Number Line Jumps | Answer |
|---|---|---|---|---|
| 1 | 34 + 25 | Tens: 30+20=50. Ones: 4+5=9. Combine: 50+9 | Start at 34. Jump 2 tens: 34→44→54. Then jump 5 ones: 54→59 | 59 |
| 2 | 48 + 31 | Tens: 40+30=70. Ones: 8+1=9. Combine: 70+9 | Start at 48. Jump 3 tens: 48→58→68→78. Then jump 1 one: 78→79 | 79 |
| 3 | 67 − 23 | Tens: 60−20=40. Ones: 7−3=4. Combine: 40+4 | Start at 67. Jump back 2 tens: 67→57→47. Then jump back 3 ones: 47→44 | 44 |
| 4 | 59 − 24 | Tens: 50−20=30. Ones: 9−4=5. Combine: 30+5 | Start at 59. Jump back 2 tens: 59→49→39. Then jump back 4 ones: 39→35 | 35 |
| 5 | 26 + 42 | Tens: 20+40=60. Ones: 6+2=8. Combine: 60+8 | Start at 26. Jump 4 tens: 26→36→46→56→66. Then jump 2 ones: 66→68 | 68 |
| 6 | 78 − 35 | Tens: 70−30=40. Ones: 8−5=3. Combine: 40+3 | Start at 78. Jump back 3 tens: 78→68→58→48. Then jump back 5 ones: 48→43 | 43 |
| 7 | 21 + 46 | Tens: 20+40=60. Ones: 1+6=7. Combine: 60+7 | Start at 21. Jump 4 tens: 21→31→41→51→61. Then jump 6 ones: 61→67 | 67 |
| 8 | 89 − 52 | Tens: 80−50=30. Ones: 9−2=7. Combine: 30+7 | Start at 89. Jump back 5 tens: 89→79→69→59→49→39. Then jump back 2 ones: 39→37 | 37 |
Grade 3 Addition and Subtraction Worksheet for Mental Math
Then, Method 1 breaks apart the tens and ones directly. Meanwhile, Method 2 uses number line jumps again, so it stays easy even when regrouping applies.
| No. | Problem | Method 1: Break Apart | Method 2: Number Line Jumps | Answer |
|---|---|---|---|---|
| 1 | 58 + 36 | Tens: 50+30=80. Ones: 8+6=14. Combine: 80+14 | Start at 58. Jump 3 tens: 58→68→78→88. Then jump 6 ones: 88→94 | 94 |
| 2 | 82 − 47 | Tens: 80−40=40. Since 2−7 is negative, subtract 5 more: 40−5 | Start at 82. Jump back 4 tens: 82→72→62→52→42. Then jump back 7 ones: 42→35 | 35 |
| 3 | 65 + 29 | Tens: 60+20=80. Ones: 5+9=14. Combine: 80+14 | Start at 65. Jump 2 tens: 65→75→85. Then jump 9 ones: 85→94 | 94 |
| 4 | 91 − 38 | Tens: 90−30=60. Since 1−8 is negative, subtract 7 more: 60−7 | Start at 91. Jump back 3 tens: 91→81→71→61. Then jump back 8 ones: 61→53 | 53 |
| 5 | 47 + 68 | Tens: 40+60=100. Ones: 7+8=15. Combine: 100+15 | Start at 47. Jump 6 tens: 47→57→67→77→87→97→107. Then jump 8 ones: 107→115 | 115 |
| 6 | 84 − 56 | Tens: 80−50=30. Since 4−6 is negative, subtract 2 more: 30−2 | Start at 84. Jump back 5 tens: 84→74→64→54→44→34. Then jump back 6 ones: 34→28 | 28 |
| 7 | 39 + 57 | Tens: 30+50=80. Ones: 9+7=16. Combine: 80+16 | Start at 39. Jump 5 tens: 39→49→59→69→79→89. Then jump 7 ones: 89→96 | 96 |
| 8 | 73 − 29 | Tens: 70−20=50. Since 3−9 is negative, subtract 6 more: 50−6 | Start at 73. Jump back 2 tens: 73→63→53. Then jump back 9 ones: 53→44 | 44 |
Grade 4 Addition and Subtraction Worksheet for Mental Math
At this stage, Method 1 splits hundreds, tens, and ones separately. Meanwhile, Method 2 rounds to the nearest ten or hundred, then adjusts.
| No. | Problem | Method 1: Hundreds-Tens-Ones | Method 2: Round and Adjust | Answer |
|---|---|---|---|---|
| 1 | 356 + 274 | Hundreds: 300+200=500. Tens: 50+70=120. Ones: 6+4=10. Combine: 630 | Round 274 to 300: 356+300=656, then subtract the extra 26: 656−26 | 630 |
| 2 | 583 − 246 | Hundreds: 500−200=300. Tens: 80−40=40. Ones: subtract 3 more since 3−6 is negative: 40−3=37. Combine: 337 | Round 246 to 250: 583−250=333, then add the extra 4 back: 333+4 | 337 |
| 3 | 467 + 328 | Hundreds: 400+300=700. Tens: 60+20=80. Ones: 7+8=15. Combine: 795 | Round 328 to 330: 467+330=797, then subtract the extra 2: 797−2 | 795 |
| 4 | 724 − 389 | Hundreds: 700−300=400. Tens: 20−80 needs borrowing, so subtract 65 total: 400−65 | Round 389 to 390: 724−390=334, then add the extra 1 back: 334+1 | 335 |
| 5 | 618 + 273 | Hundreds: 600+200=800. Tens: 10+70=80. Ones: 8+3=11. Combine: 891 | Round 273 to 270: 618+270=888, then add the missing 3: 888+3 | 891 |
| 6 | 813 − 456 | Hundreds: 800−400=400. Tens and ones need borrowing, so subtract 43 more: 400−43 | Round 456 to 460: 813−460=353, then add the extra 4 back: 353+4 | 357 |
| 7 | 274 + 519 | Hundreds: 200+500=700. Tens: 70+10=80. Ones: 4+9=13. Combine: 793 | Round 519 to 520: 274+520=794, then subtract the extra 1: 794−1 | 793 |
| 8 | 907 − 418 | Hundreds: 900−400=500. Tens and ones need borrowing, so subtract 11 more: 500−11 | Round 418 to 420: 907−420=487, then add the extra 2 back: 487+2 | 489 |
Grade 5 Worksheet
Similarly, Method 1 breaks each number into a hundreds part plus the rest. Meanwhile, Method 2 rounds to the nearest ten or hundred for a quicker path.
| No. | Problem | Method 1: Hundreds Plus Rest | Method 2: Round and Adjust | Answer |
|---|---|---|---|---|
| 1 | 647 + 385 | Hundreds: 600+300=900. Rest: 47+85=132. Combine: 1032 | Round 385 to 400: 647+400=1047, then subtract the extra 15: 1047−15 | 1032 |
| 2 | 932 − 468 | Hundreds: 900−400=500. Rest needs borrowing, so subtract 36 more: 500−36 | Round 468 to 470: 932−470=462, then add the extra 2 back: 462+2 | 464 |
| 3 | 519 + 276 | Hundreds: 500+200=700. Rest: 19+76=95. Combine: 795 | Round 276 to 280: 519+280=799, then subtract the extra 4: 799−4 | 795 |
| 4 | 805 − 347 | Hundreds: 800−300=500. Rest needs borrowing, so subtract 42 more: 500−42 | Round 347 to 350: 805−350=455, then add the extra 3 back: 455+3 | 458 |
| 5 | 738 + 254 | Hundreds: 700+200=900. Rest: 38+54=92. Combine: 992 | Round 254 to 250: 738+250=988, then add the missing 4: 988+4 | 992 |
| 6 | 921 − 573 | Hundreds: 900−500=400. Rest needs borrowing, so subtract 52 more: 400−52 | Round 573 to 600: 921−600=321, then add the extra 27 back: 321+27 | 348 |
| 7 | 486 + 359 | Hundreds: 400+300=700. Rest: 86+59=145. Combine: 845 | Round 359 to 360: 486+360=846, then subtract the extra 1: 846−1 | 845 |
| 8 | 764 − 289 | Hundreds: 700−200=500. Rest needs borrowing, so subtract 25 more: 500−25 | Round 289 to 290: 764−290=474, then add the extra 1 back: 474+1 | 475 |
For Grade 6 Worksheet
Finally, Method 1 solves the problem left to right. Meanwhile, Method 2 groups all the additions and all the subtractions first, then combines the two group totals.
| No. | Problem | Method 1: Left to Right | Method 2: Group by Operation | Answer |
|---|---|---|---|---|
| 1 | 246 + 358 − 129 | First: 246+358=604. Then: 604−129 | Add first: 246+358=604. Subtract: 604−129 | 475 |
| 2 | 517 − 268 + 344 | First: 517−268=249. Then: 249+344 | Add group: 517+344=861. Subtract: 861−268 | 593 |
| 3 | 385 + 217 − 196 | First: 385+217=602. Then: 602−196 | Add first: 385+217=602. Subtract: 602−196 | 406 |
| 4 | 730 − 384 + 255 | First: 730−384=346. Then: 346+255 | Add group: 730+255=985. Subtract: 985−384 | 601 |
| 5 | 462 + 289 − 337 | First: 462+289=751. Then: 751−337 | Add first: 462+289=751. Subtract: 751−337 | 414 |
| 6 | 618 − 245 + 173 | First: 618−245=373. Then: 373+173 | Add group: 618+173=791. Subtract: 791−245 | 546 |
| 7 | 356 + 219 − 148 | First: 356+219=575. Then: 575−148 | Add first: 356+219=575. Subtract: 575−148 | 427 |
| 8 | 682 − 317 + 205 | First: 682−317=365. Then: 365+205 | Add group: 682+205=887. Subtract: 887−317 | 570 |
Conclsion
Overall, every table with the addition and subtraction worksheet above proves the same point twice. First, Method 1 reaches the answer one way. Then, Method 2 reaches the same answer a different way. Therefore, whichever method feels faster, the result stays accurate every time. In short, this two-method approach makes mental math flexible, reliable, and easy to check.
