Revision of First Term’s Topic Basic 6 Mathematics Lesson Note

WHOLE NUMBERS REVISION

Place Value and Reading Numbers

Remember: Each digit has a place and a value

Example: 45,678,923

• 4 is in ten millions place = 40,000,000
• 5 is in millions place = 5,000,000
• 6 is in hundred thousands place = 600,000

Exercise A – Place Value Review

Write these numbers in words:

1. 8,456,789 = ___________________________
2. 25,000,600 = ___________________________
3. 340,007,000 = ___________________________

Write in figures:

1. Fifteen million, six hundred thousand = _______________
2. Seven billion, two hundred million = _______________

Basic Operations with Whole Numbers

Addition and Subtraction Review

Example: 456,789 + 234,567 = 691,356 Example: 800,000 – 234,567 = 565,433

Multiplication and Division Review

Example: 2,456 × 78 = 191,568 Example: 15,678 ÷ 23 = 681 R 15

Exercise B – Whole Number Operations

Solve these problems:

1. 567,890 + 234,567 = __________
2. 1,000,000 – 456,789 = __________
3. 1,234 × 56 = __________
4. 8,456 ÷ 34 = __________
5. 234 × 67 + 189 = __________

DECIMAL NUMBERS REVISION

Understanding Decimals

Place Value in Decimals:

• 23.456
• 2 = tens, 3 = units, 4 = tenths, 5 = hundredths, 6 = thousandths

Converting Between Fractions and Decimals

Examples:

• 1/2 = 0.5
• 3/4 = 0.75
• 0.2 = 1/5
• 0.25 = 1/4

Exercise C – Decimal Basics

Convert to decimals:

1. 1/4 = ______
2. 3/5 = ______
3. 7/8 = ______

Convert to fractions:

1. 0.6 = ______
2. 0.125 = ______

Operations with Decimals

Addition and Subtraction

Remember: Line up decimal points!

Example: 23.45 + 67.8 + 9.456 = 100.706

Multiplication and Division

Example: 12.5 × 4.6 = 57.5 Example: 84.6 ÷ 2.3 = 36.8

Exercise D – Decimal Operations

Solve these problems:

1. 45.67 + 23.8 + 9.456 = __________
2. 100.5 – 67.89 = __________
3. 12.5 × 3.4 = __________
4. 91.8 ÷ 1.8 = __________
5. 67.8 + 23.45 – 34.56 = __________

FRACTIONS REVISION

Types of Fractions

Proper Fractions: 3/4, 2/5, 7/8 Improper Fractions: 5/3, 8/5, 11/4 Mixed Numbers: 1 1/2, 2 3/4, 5 2/3

Converting Between Types

Example: 2 3/4 = (2×4+3)/4 = 11/4 Example: 13/5 = 2 3/5

Exercise E – Fraction Types

Convert to improper fractions:

1. 2 1/3 = ______
2. 3 2/5 = ______
3. 1 5/8 = ______

Convert to mixed numbers:

1. 11/4 = ______
2. 23/7 = ______

Fraction Operations

Addition and Subtraction

Same denominators: 2/7 + 3/7 = 5/7 Different denominators: 1/3 + 1/4 = 4/12 + 3/12 = 7/12

Multiplication and Division

Multiplication: 2/3 × 3/4 = 6/12 = 1/2 Division: 2/3 ÷ 1/4 = 2/3 × 4/1 = 8/3

Exercise F – Fraction Operations

Solve these problems:

1. 1/2 + 1/3 = ______
2. 3/4 – 1/6 = ______
3. 2/3 × 3/5 = ______
4. 3/4 ÷ 1/2 = ______
5. 1 1/2 + 2 1/4 = ______

MIXED REVISION EXERCISES

Exercise G – Mixed Operations

Solve using order of operations:

1. 15 + 3 × 4 – 8 = ______
2. (24 – 8) ÷ 4 + 5 = ______
3. 2.5 + 1.8 × 3 = ______
4. 1/2 + 1/3 × 6 = ______
5. 45 – (12 + 8) ÷ 5 = ______

Exercise H – Real Life Problems

Solve these word problems:

1. Shopping Bill: Tunde bought items costing ₦2,450.75, ₦1,890.50, and ₦3,670.25. How much did he spend in total? Answer: ₦__________
2. Class Average: Five students scored 78, 85, 92, 67, and 88 in a test. What is their average score? Answer: __________
3. Sharing Money: ₦15,600 is shared equally among 12 students. How much does each student get? Answer: ₦__________
4. Cooking Recipe: A recipe needs 2 1/4 cups of flour. If Mama wants to make 1 1/2 times the recipe, how much flour does she need? Answer: ______ cups

Exercise I – Approximation and Estimation

Estimate first, then calculate exactly:

1. 567 + 234 + 189 Estimate: ______ Exact: ______
2. 789 – 345 Estimate: ______ Exact: ______
3. 23 × 47 Estimate: ______ Exact: ______
4. 23.7 + 45.8 Estimate: ______ Exact: ______

Exercise J – L.C.M and H.C.F Review

Find L.C.M and H.C.F:

1. Numbers: 18 and 24 L.C.M: ______ H.C.F: ______
2. Numbers: 15, 20, 25 L.C.M: ______ H.C.F: ______
3. Real Problem: Three bells ring every 6, 8, and 12 minutes. If they ring together at 9:00 AM, when will they ring together again? Answer: ______

Exercise K – Scale Drawing Review

Solve these scale problems:

1. A room 8 meters long is drawn using scale 1:200. What is the drawing length? Answer: ______ cm
2. On a map with scale 1:50,000, two towns are 6 cm apart. What is the real distance? Answer: ______ km

Answer Key

Exercise A:

1. Eight million, four hundred and fifty-six thousand, seven hundred and eighty-nine
2. Twenty-five million, six hundred
3. Three hundred and forty million, seven thousand
4. 15,600,000
5. 7,200,000,000

Exercise B:

1. 802,457
2. 543,211
3. 69,104
4. 248 R 24
5. 15,967

Exercise C:

1. 0.25
2. 0.6
3. 0.875
4. 3/5
5. 1/8

Exercise D:

1. 78.926
2. 32.61
3. 42.5
4. 51
5. 56.69

Exercise E:

1. 7/3
2. 17/5
3. 13/8
4. 2 3/4
5. 3 2/7

Exercise F:

1. 5/6
2. 7/12
3. 2/5
4. 1 1/2
5. 3 3/4

Exercise G:

1. 19
2. 9
3. 7.9
4. 2 1/2
5. 41

Exercise H:

1. ₦8,011.50
2. 82
3. ₦1,300
4. 3 3/8 cups

Exercise I:

1. Est: 1,000, Exact: 990
2. Est: 450, Exact: 444
3. Est: 1,000, Exact: 1,081
4. Est: 70, Exact: 69.5

Exercise J:

1. L.C.M: 72, H.C.F: 6
2. L.C.M: 300, H.C.F: 5
3. 9:24 AM

Exercise K:

1. 4 cm
2. 3 km