Mathematics - Term 1 - Week 3

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. To visualize these operations, we can use number lines, counters, or drawings. For example, if we add 3 + 5, we can start at 3 on a number line and move 5 steps to the right, landing on 8. Conversely, for subtraction, if we have 8 and subtract 5, we can start at 8 and move 5 steps to the left, landing on 3.

Let's solve 27 + 45. We can break this down into tens and units: 20 + 40 = 60 and 7 + 5 = 12. Now, we add these results together: 60 + 12 = 72. Therefore, 27 + 45 = 72.

Consider the problem 82 - 29. We can also break this down: 82 - 20 = 62 and then 62 - 9 = 53. Thus, 82 - 29 = 53.

Now, let's try some guided practice together. Solve 34 + 19. Start by adding the tens: 30 + 10 = 40, and then the units: 4 + 9 = 13. Combine these results: 40 + 13 = 53. Next, let's solve 56 - 23. Break it down: 56 - 20 = 36 and then 36 - 3 = 33. So, 56 - 23 = 33.

Now it's your turn! Solve the following problems on your own: 45 + 36 and 91 - 47. Remember to show your working clearly. After you finish, we will review the answers together.

• 92
• 82
• 72
• 94

Answer: 92

58 + 34 equals 92 when you add the tens and units separately.

• 44
• 54
• 64
• 34

Answer: 44

73 - 29 equals 44 when you subtract 20 and then 9.

Answer: 42

15 + 27 equals 42 when you add the units and tens.

Answer: 44

100 - 56 equals 44.

• 83
• 93
• 73
• 63

Answer: 93

64 + 29 equals 93 when you add the tens and units.

• 51
• 61
• 71
• 41

Answer: 51

88 - 37 equals 51 when you subtract 30 and then 7.

Answer: 67

22 + 45 equals 67.

Answer: 57

75 - 18 equals 57.