3
Different sums, same answer
Joyful Mathematics: Chapter 5
GoalSee that different additions can make the same number.
New words
same answer · the same totalmatch · find two that go togetherpair · two numbers that are added
Explanation
Different sums can have the same answer. 3 + 4 = 7. 5 + 2 = 7. 6 + 1 = 7. All three make 7. Look at the dots. The colours are different, but there are 7 dots every time.
Worked examples
5 + 2 = 7. The frame shows 5 dots and 2 dots.
6 + 1 = 7. The frame shows 6 dots and 1 dot.
1 + 4 and 3 + 2 both make 5.
Class activity
Sum cards. Write these sums on small paper slips: 1 + 5, 2 + 4, 3 + 3, 1 + 7, 2 + 6, 4 + 4. Mix the slips. Sort them into two piles: one pile with the answer 6 and one pile with the answer 8.
Practice
1
Which sum makes 8: 4 + 4, 5 + 4 or 6 + 1?
4 + 4.
2
Write the sum for the dots.
2 + 5 = 7.
3
Do 3 + 5 and 6 + 2 have the same answer?
Yes. Both make 8.
4
Imran has 2 oranges. Lakshmi has 6 oranges. How many oranges altogether?
8.
5
Fill in: 4 + ___ = 9
5.