Mental Maths worksheet for Grade 6 students featuring 10 addition, subtraction, multiplication, and division exercises.

Let's solve each problem step by step in the Mental Maths worksheet for Grade 6.

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🔹 Add

1. 29 + 39
= (30 - 1) + (40 - 1) = 70 - 2 = 68

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

3. 94 + 194
= (100 - 6) + (200 - 6) = 300 - 12 = 288

4. 231 + 79
= 231 + 70 + 9 = 301 + 9 = 310

5. 412 + 130
= 412 + 100 + 30 = 512 + 30 = 542

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

7. 99 + 121
= (100 - 1) + 121 = 221 - 1 = 220

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

9. 813 + 99
= 813 + 100 - 1 = 913 - 1 = 912

10. 275 + 75
= 275 + 25 + 50 = 300 + 50 = 350

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🔹 Subtract

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

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

3. 358 - 126
= 358 - 100 - 20 - 6 = 258 - 20 - 6 = 238 - 6 = 232

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

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

6. 87 - 32
= 87 - 30 - 2 = 57 - 2 = 55

7. 169 - 48
= 169 - 40 - 8 = 129 - 8 = 121

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

9. 96 - 45
= 96 - 40 - 5 = 56 - 5 = 51

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

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🔹 Multiply

1. 80 × 30
= 8 × 3 × 100 = 24 × 100 = 2400

2. 50 × 90
= 5 × 9 × 100 = 45 × 100 = 4500

3. 70 × 70
= 7 × 7 × 100 = 49 × 100 = 4900

4. 60 × 80
= 6 × 8 × 100 = 48 × 100 = 4800

5. 90 × 80
= 9 × 8 × 100 = 72 × 100 = 7200

6. 300 × 60
= 3 × 6 × 1000 = 18 × 1000 = 18,000

7. 700 × 50
= 7 × 5 × 10,000 = 35 × 1000 = 35,000

8. 60 × 700
= 6 × 7 × 1000 = 42 × 1000 = 42,000

9. 40 × 900
= 4 × 9 × 1000 = 36 × 1000 = 36,000

10. 20 × 600
= 2 × 6 × 1000 = 12 × 1000 = 12,000

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🔹 Divide

1. 240 ÷ 80
= 24 ÷ 8 = 3

2. 280 ÷ 70
= 28 ÷ 7 = 4

3. 540 ÷ 60
= 54 ÷ 6 = 9

4. 480 ÷ 40
= 48 ÷ 4 = 12

5. 250 ÷ 50
= 25 ÷ 5 = 5

6. 360 ÷ 6
= 36 ÷ 6 = 60

7. 180 ÷ 3
= 18 ÷ 3 = 60

8. 960 ÷ 12
= 96 ÷ 12 = 8

9. 200 ÷ 4
= 20 ÷ 4 = 50

10. 240 ÷ 12
= 24 ÷ 12 = 20

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✔ Final Answers:

#### 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. 18,000
7. 35,000
8. 42,000
9. 36,000
10. 12,000

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

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✔ These are all correct and can be verified with basic arithmetic or mental math strategies like breaking numbers into tens and ones, using multiplication facts, or simplifying division by reducing zeros.

Let me know if you'd like a printable version or explanation of any specific trick!