Mathematics - Term 2 - Week 1

Addition is the process of finding the total or sum by combining two or more numbers. Subtraction, on the other hand, involves finding the difference between numbers by taking one number away from another. To visualize these operations, we can use number lines, counters, or drawings. For example, if we have 5 apples and we add 3 more, we can represent this on a number line by starting at 5 and moving 3 steps to the right, landing on 8. Conversely, if we have 8 apples and give away 3, we can move 3 steps to the left on the number line to find that we have 5 apples left.

Let's solve the problem: 27 + 45. We can break this down into simpler parts. First, add the tens: 20 + 40 = 60. Next, add the units: 7 + 5 = 12. Now, combine these results: 60 + 12 = 72. Therefore, 27 + 45 = 72.

Consider the subtraction problem: 56 - 29. Start by subtracting the tens: 50 - 20 = 30. Then, subtract the units: 6 - 9. Since we cannot subtract 9 from 6, we need to borrow 1 from the tens, making it 16 - 9 = 7. Now, combine the results: 30 + 7 = 27. Thus, 56 - 29 = 27.

Now, let's practice addition together. Solve the following: 34 + 28. Start by adding the tens: 30 + 20 = 50. Next, add the units: 4 + 8 = 12. Combine these results: 50 + 12 = 62. Discuss your thought process with a partner and share how you approached the problem.

Let's work on a subtraction problem: 73 - 46. First, subtract the tens: 70 - 40 = 30. Then, subtract the units: 3 - 6. Since we cannot do this directly, we borrow from the tens, making it 13 - 6 = 7. Combine the results: 30 + 7 = 27. Share your solution with the class and explain how you handled the borrowing.

Now it's your turn! Solve the following problems independently: 45 + 37 and 82 - 29. Show all your working steps clearly. After completing the problems, check your answers with a partner and discuss any mistakes you made and how you can correct them.

• 42
• 32
• 22
• 52

Answer: 42

Adding 15 and 27 gives a total of 42.

• 35
• 45
• 55
• 25

Answer: 35

Subtracting 29 from 64 results in 35.

Answer: 92

Adding 58 and 34 gives a total of 92.

Answer: 43

Subtracting 47 from 90 results in 43.

• 42
• 32
• 52
• 22

Answer: 42

The sum of 23 and 19 is 42.

• 47
• 57
• 67
• 37

Answer: 47

Subtracting 28 from 75 gives 47.

Answer: 55

The sum of 33 and 22 is 55.

Answer: 44

Subtracting 56 from 100 results in 44.