Mental Maths worksheet with exercises on fractions, decimals, percentages, order of operations, rounding, and mixed calculations.
A colorful educational worksheet titled "Mental Maths" from Stambo Resources, featuring sections on Fraction/Decimal/Percent conversion, BEDMAS/BIMDAS calculations, rounding to one decimal place, percentage of a number, and mixed math problems.
PNG
1120×776
47.4 KB
Free · Personal Use
Quality Assured by Worksheets Library Team
Reviewed for educational accuracy and age-appropriateness
ID: #268499
⭐
Show Answer Key & Explanations
Step-by-step solution for: Grade 6 Maths - slamboresources
▼
Show Answer Key & Explanations
Step-by-step solution for: Grade 6 Maths - slamboresources
Let’s solve each section step by step.
---
Fraction / Decimal / Percent Table
We need to fill in missing values using conversions:
1. 1/4
→ Decimal: 1 ÷ 4 = 0.25
→ Percent: 0.25 × 100 = 25%
2. Decimal 0.33 (approximate for 1/3)
→ Fraction: ≈ 1/3
→ Percent: 0.33 × 100 = 33%
3. Percent 80%
→ Decimal: 80 ÷ 100 = 0.8
→ Fraction: 80/100 = 4/5
4. 2/5
→ Decimal: 2 ÷ 5 = 0.4
→ Percent: 0.4 × 100 = 40%
5. Decimal 0.75
→ Fraction: 75/100 = 3/4
→ Percent: 0.75 × 100 = 75%
6. Percent 55%
→ Decimal: 55 ÷ 100 = 0.55
→ Fraction: 55/100 = 11/20
---
BEDMAS / BIMDAS Problems
Remember: Brackets, Exponents, Division/Multiplication (left to right), Addition/Subtraction (left to right)
1. 15 + 5 × 30
→ Multiply first: 5 × 30 = 150
→ Then add: 15 + 150 = 165
2. 27 + 9 × 8
→ 9 × 8 = 72
→ 27 + 72 = 99
3. 60 - 5 × 12
→ 5 × 12 = 60
→ 60 - 60 = 0
4. 36 ÷ 6 × 11
→ Left to right: 36 ÷ 6 = 6
→ 6 × 11 = 66
5. 8 × 8 ÷ 2
→ 8 × 8 = 64
→ 64 ÷ 2 = 32
6. 35 + 10 × 90
→ 10 × 90 = 900
→ 35 + 900 = 935
---
Round to 1 decimal place
Look at the second decimal digit. If it’s 5 or more, round up the first decimal.
1. 2.75 → second digit is 5 → round up → 2.8
2. 4.23 → second digit is 3 → keep → 4.2
3. 8.65 → second digit is 5 → round up → 8.7
4. 7.23 → second digit is 3 → keep → 7.2
5. 9.67 → second digit is 7 → round up → 9.7
6. 1.45 → second digit is 5 → round up → 1.5
7. 1.547 → look at hundredths (4) and thousandths (7). Since we’re rounding to 1 decimal, look at second decimal (4) — but wait! Actually, to round to 1 decimal, look at the *second* decimal digit: 4 → less than 5 → so 1.5? Wait — no:
Wait — 1.547:
First decimal = 5
Second decimal = 4 → which is less than 5 → so we do NOT round up → 1.5
But actually — let me double-check:
Rounding 1.547 to 1 decimal place:
Look at the digit after the first decimal → that’s the 4 (in hundredths place). Since 4 < 5, we leave the 5 as is → 1.5
8. 95.235 → first decimal = 2, second = 3 → 3 < 5 → 95.2
9. 67.184 → first decimal = 1, second = 8 → 8 ≥ 5 → round up 1 to 2 → 67.2
10. 77.415 → first decimal = 4, second = 1 → 1 < 5 → 77.4
11. 82.653 → first decimal = 6, second = 5 → round up → 82.7
12. 9.645 → first decimal = 6, second = 4 → 4 < 5 → 9.6
Wait — correction on #7: 1.547 → to 1 decimal:
The number is 1.5|47 → the part after the first decimal is .47 → since 4 < 5, we don’t round up → still 1.5
Actually, standard rule: To round to 1 decimal, look at the *second* decimal digit only.
So:
7. 1.547 → second decimal is 4 → so 1.5
All others seem correct.
---
Percentage OF A NUMBER
This means: find that percent of the given number.
Example: 10% of 80 = 80 × 0.10 = 8
Let’s compute:
10% column:
- 10% of 80 = 8
- 10% of 40 = 4
- 10% of 25 = 2.5
20% column:
- 20% of 30 = 30 × 0.2 = 6
- 20% of 120 = 120 × 0.2 = 24
- 20% of 55 = 55 × 0.2 = 11
30% column:
- 30% of 60 = 60 × 0.3 = 18
- 30% of 90 = 90 × 0.3 = 27
- 30% of 120 = 120 × 0.3 = 36
---
Mixed Problems
1. 14 × 3 = 42
2. 84 ÷ 12 = 7
3. 85 + 85 = 170
4. 185 - 78 = 107
5. 6 × 25 = 150
6. 33 × 3 = 99
7. 132 ÷ 11 = 12
8. 79 + 79 = 158
9. 241 - 80 = 161
10. 32 × 4 = 128
---
Final Answer:
Fraction / Decimal / Percent Table:
| Fraction | Decimal | Percent |
|----------|---------|---------|
| 1/4 | 0.25 | 25% |
| 1/3 | 0.33 | 33% |
| 4/5 | 0.8 | 80% |
| 2/5 | 0.4 | 40% |
| 3/4 | 0.75 | 75% |
| 11/20 | 0.55 | 55% |
BEDMAS / BIMDAS Answers:
1. 165
2. 99
3. 0
4. 66
5. 32
6. 935
Round to 1 decimal place:
1. 2.8
2. 4.2
3. 8.7
4. 7.2
5. 9.7
6. 1.5
7. 1.5
8. 95.2
9. 67.2
10. 77.4
11. 82.7
12. 9.6
Percentage OF A NUMBER:
10%: 8, 4, 2.5
20%: 6, 24, 11
30%: 18, 27, 36
Mixed:
1. 42
2. 7
3. 170
4. 107
5. 150
6. 99
7. 12
8. 158
9. 161
10. 128
---
Fraction / Decimal / Percent Table
We need to fill in missing values using conversions:
1. 1/4
→ Decimal: 1 ÷ 4 = 0.25
→ Percent: 0.25 × 100 = 25%
2. Decimal 0.33 (approximate for 1/3)
→ Fraction: ≈ 1/3
→ Percent: 0.33 × 100 = 33%
3. Percent 80%
→ Decimal: 80 ÷ 100 = 0.8
→ Fraction: 80/100 = 4/5
4. 2/5
→ Decimal: 2 ÷ 5 = 0.4
→ Percent: 0.4 × 100 = 40%
5. Decimal 0.75
→ Fraction: 75/100 = 3/4
→ Percent: 0.75 × 100 = 75%
6. Percent 55%
→ Decimal: 55 ÷ 100 = 0.55
→ Fraction: 55/100 = 11/20
---
BEDMAS / BIMDAS Problems
Remember: Brackets, Exponents, Division/Multiplication (left to right), Addition/Subtraction (left to right)
1. 15 + 5 × 30
→ Multiply first: 5 × 30 = 150
→ Then add: 15 + 150 = 165
2. 27 + 9 × 8
→ 9 × 8 = 72
→ 27 + 72 = 99
3. 60 - 5 × 12
→ 5 × 12 = 60
→ 60 - 60 = 0
4. 36 ÷ 6 × 11
→ Left to right: 36 ÷ 6 = 6
→ 6 × 11 = 66
5. 8 × 8 ÷ 2
→ 8 × 8 = 64
→ 64 ÷ 2 = 32
6. 35 + 10 × 90
→ 10 × 90 = 900
→ 35 + 900 = 935
---
Round to 1 decimal place
Look at the second decimal digit. If it’s 5 or more, round up the first decimal.
1. 2.75 → second digit is 5 → round up → 2.8
2. 4.23 → second digit is 3 → keep → 4.2
3. 8.65 → second digit is 5 → round up → 8.7
4. 7.23 → second digit is 3 → keep → 7.2
5. 9.67 → second digit is 7 → round up → 9.7
6. 1.45 → second digit is 5 → round up → 1.5
7. 1.547 → look at hundredths (4) and thousandths (7). Since we’re rounding to 1 decimal, look at second decimal (4) — but wait! Actually, to round to 1 decimal, look at the *second* decimal digit: 4 → less than 5 → so 1.5? Wait — no:
Wait — 1.547:
First decimal = 5
Second decimal = 4 → which is less than 5 → so we do NOT round up → 1.5
But actually — let me double-check:
Rounding 1.547 to 1 decimal place:
Look at the digit after the first decimal → that’s the 4 (in hundredths place). Since 4 < 5, we leave the 5 as is → 1.5
8. 95.235 → first decimal = 2, second = 3 → 3 < 5 → 95.2
9. 67.184 → first decimal = 1, second = 8 → 8 ≥ 5 → round up 1 to 2 → 67.2
10. 77.415 → first decimal = 4, second = 1 → 1 < 5 → 77.4
11. 82.653 → first decimal = 6, second = 5 → round up → 82.7
12. 9.645 → first decimal = 6, second = 4 → 4 < 5 → 9.6
Wait — correction on #7: 1.547 → to 1 decimal:
The number is 1.5|47 → the part after the first decimal is .47 → since 4 < 5, we don’t round up → still 1.5
Actually, standard rule: To round to 1 decimal, look at the *second* decimal digit only.
So:
7. 1.547 → second decimal is 4 → so 1.5
All others seem correct.
---
Percentage OF A NUMBER
This means: find that percent of the given number.
Example: 10% of 80 = 80 × 0.10 = 8
Let’s compute:
10% column:
- 10% of 80 = 8
- 10% of 40 = 4
- 10% of 25 = 2.5
20% column:
- 20% of 30 = 30 × 0.2 = 6
- 20% of 120 = 120 × 0.2 = 24
- 20% of 55 = 55 × 0.2 = 11
30% column:
- 30% of 60 = 60 × 0.3 = 18
- 30% of 90 = 90 × 0.3 = 27
- 30% of 120 = 120 × 0.3 = 36
---
Mixed Problems
1. 14 × 3 = 42
2. 84 ÷ 12 = 7
3. 85 + 85 = 170
4. 185 - 78 = 107
5. 6 × 25 = 150
6. 33 × 3 = 99
7. 132 ÷ 11 = 12
8. 79 + 79 = 158
9. 241 - 80 = 161
10. 32 × 4 = 128
---
Final Answer:
Fraction / Decimal / Percent Table:
| Fraction | Decimal | Percent |
|----------|---------|---------|
| 1/4 | 0.25 | 25% |
| 1/3 | 0.33 | 33% |
| 4/5 | 0.8 | 80% |
| 2/5 | 0.4 | 40% |
| 3/4 | 0.75 | 75% |
| 11/20 | 0.55 | 55% |
BEDMAS / BIMDAS Answers:
1. 165
2. 99
3. 0
4. 66
5. 32
6. 935
Round to 1 decimal place:
1. 2.8
2. 4.2
3. 8.7
4. 7.2
5. 9.7
6. 1.5
7. 1.5
8. 95.2
9. 67.2
10. 77.4
11. 82.7
12. 9.6
Percentage OF A NUMBER:
10%: 8, 4, 2.5
20%: 6, 24, 11
30%: 18, 27, 36
Mixed:
1. 42
2. 7
3. 170
4. 107
5. 150
6. 99
7. 12
8. 158
9. 161
10. 128
Parent Tip: Review the logic above to help your child master the concept of math worksheet for class 6.