Grade 6 Mental Maths worksheet featuring 10 problems each for addition, subtraction, multiplication, and division.

Let’s solve each problem step by step. I’ll go column by column: Add, Subtract, Multiply, Divide.

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ADD Column:

1. 29 + 39
→ 20 + 30 = 50; 9 + 9 = 18 → 50 + 18 = 68

2. 86 + 42
→ 80 + 40 = 120; 6 + 2 = 8 → 120 + 8 = 128

3. 94 + 194
→ 94 + 200 = 294, minus 6 = 288 (or 90+190=280, 4+4=8 → 288)

4. 231 + 79
→ 231 + 80 = 311, minus 1 = 310

5. 412 + 130
→ 400 + 100 = 500; 12 + 30 = 42 → 542

6. 351 + 251
→ 350 + 250 = 600; 1 + 1 = 2 → 602

7. 99 + 121
→ 100 + 121 = 221, minus 1 = 220

8. 517 + 217
→ 500 + 200 = 700; 17 + 17 = 34 → 734

9. 813 + 99
→ 813 + 100 = 913, minus 1 = 912

10. 275 + 75
→ 275 + 25 = 300; +50 more = 350

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SUBTRACT Column:

1. 624 - 84
→ 624 - 80 = 544; 544 - 4 = 540

2. 120 - 65
→ 120 - 60 = 60; 60 - 5 = 55

3. 358 - 126
→ 358 - 100 = 258; 258 - 26 = 232

4. 836 - 95
→ 836 - 100 = 736; +5 = 741

5. 312 - 105
→ 312 - 100 = 212; 212 - 5 = 207

6. 87 - 32
→ 80 - 30 = 50; 7 - 2 = 5 → 55

7. 169 - 48
→ 169 - 50 = 119; +2 = 121

8. 254 - 89
→ 254 - 90 = 164; +1 = 165

9. 96 - 45
→ 90 - 40 = 50; 6 - 5 = 1 → 51

10. 326 - 83
→ 326 - 80 = 246; 246 - 3 = 243

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MULTIPLY Column:

1. 80 × 30
→ 8 × 3 = 24; add two zeros → 2400

2. 50 × 90
→ 5 × 9 = 45; add two zeros → 4500

3. 70 × 70
→ 7 × 7 = 49; add two zeros → 4900

4. 60 × 80
→ 6 × 8 = 48; add two zeros → 4800

5. 90 × 80
→ 9 × 8 = 72; add two zeros → 7200

6. 300 × 60
→ 3 × 6 = 18; add three zeros → 18000

7. 700 × 50
→ 7 × 5 = 35; add three zeros → 35000

8. 60 × 700
→ 6 × 7 = 42; add three zeros → 42000

9. 40 × 900
→ 4 × 9 = 36; add three zeros → 36000

10. 20 × 600
→ 2 × 6 = 12; add three zeros → 12000

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DIVIDE Column:

1. 240 ÷ 80
→ 24 ÷ 8 = 3 → 3

2. 280 ÷ 70
→ 28 ÷ 7 = 4 → 4

3. 540 ÷ 60
→ 54 ÷ 6 = 9 → 9

4. 480 ÷ 40
→ 48 ÷ 4 = 12 → 12

5. 250 ÷ 50
→ 25 ÷ 5 = 5 → 5

6. 360 ÷ 6
→ 36 ÷ 6 = 6; add zero? Wait — 360 ÷ 6 = 60

7. 180 ÷ 3
→ 18 3 = 6; add zero → 60

8. 960 ÷ 12
→ 96 ÷ 12 = 8; add zero → 80

9. 200 ÷ 4
→ 20 ÷ 4 = 5; add zero → 50

10. 240 ÷ 12
→ 24 ÷ 12 = 2; add zero → 20

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Final Answer:

Add:
1. 68
2. 128
3. 288
4. 310
5. 542
6. 602
7. 220
8. 734
9. 912
10. 350

Subtract:
1. 540
2. 55
3. 232
4. 741
5. 207
6. 55
7. 121
8. 165
9. 51
10. 243

Multiply:
1. 2400
2. 4500
3. 4900
4. 4800
5. 7200
6. 18000
7. 35000
8. 42000
9. 36000
10. 12000

Divide:
1. 3
2. 4
3. 9
4. 12
5. 5
6. 60
7. 60
8. 80
9. 50
10. 20