Mathematics - Term 4 - Week 7

Addition is the process of combining two or more numbers to find a total, while subtraction involves taking one number away from another to find the difference. Both operations are fundamental in mathematics and can be represented using visual models such as number lines, counters, or base ten blocks. For example, if we have 5 apples and we add 3 more, we can visualize this by moving 3 steps forward on a number line starting from 5, landing on 8. Conversely, if we have 8 apples and we subtract 3, we can move 3 steps back to find that we have 5 apples left.

Let's solve the problem: 47 + 36. We can break this down into tens and units. First, add the tens: 40 + 30 = 70. Next, add the units: 7 + 6 = 13. Now, combine these results: 70 + 13 = 83. Therefore, 47 + 36 = 83.

Consider the subtraction problem: 92 - 47. We can also break this down. Start with the tens: 90 - 40 = 50. Then, subtract the units: 2 - 7. Since we cannot subtract 7 from 2, we need to borrow 1 from the tens, making it 12 - 7 = 5. Now, combine the results: 50 - 0 = 50, so 92 - 47 = 45.

Now, let's practice together. Solve 58 + 24. Start by adding the tens: 50 + 20. What do you get? Next, add the units: 8 + 4. Combine your results to find the total.

Next, try this subtraction problem: 75 - 29. Begin by subtracting the tens: 70 - 20. What is your answer? Then, subtract the units: 5 - 9. Remember to borrow if needed. Share your final answer with the class.

Now it's your turn! Solve the following problems on your own: 1) 64 + 37, 2) 81 - 46, 3) 29 + 58, 4) 100 - 75. Show all your working steps clearly. Once you finish, check your answers with a partner and discuss any mistakes.

• 53
• 63
• 73
• 83

Answer: 63

34 + 29 equals 63 when you add the tens and units separately.

• 48
• 58
• 68
• 78

Answer: 48

85 - 37 equals 48 after borrowing from the tens.

Answer: 75

Adding 56 and 19 gives you 75.

Answer: 45

Subtracting 45 from 90 results in 45.

• 80
• 90
• 100
• 110

Answer: 90

72 + 18 equals 90.

• 34
• 44
• 54
• 64

Answer: 44

100 minus 56 equals 44.

Answer: 75

Adding 48 and 27 gives you 75.

Answer: 44

66 minus 22 equals 44.