3
Sort it, then add it
Discover Mathematics: Chapter 5
GoalSort things by colour or shape, and add two groups within 10.
New words
sort · put alike things togetheradd · put two groups together to find how manyin all · the whole amount togetherplus · the word for putting together
Explanation
To sort, we put things that are alike together. We can sort by colour or by shape. Then we count each group. To add, we put two groups together and count them all. 3 apples and 2 apples are 5 apples in all. We write 3 + 2 = 5. The plus sign means put together. The equals sign means the same as.
Worked examples
Tamer sorts the things from the market by colour. Red: the apple, the tomato and the strawberry. Yellow: the banana and the lemon.
Mina sorts shapes: 2 circles, 2 squares and 1 triangle.
Yara has 4 oranges. Her grandmother gives her 3 more. 4 + 3 = 7, so she has 7 oranges in all.
Class activity
Sorting game. Put 8 or 10 small things on a mat, such as socks, spoons or buttons. The child sorts them by colour, then by size, and counts each group. Then a grown-up joins two groups and the child says how many there are in all.
Practice
1
Which one is not yellow?
The tomato
2
What is 5 + 3? Count both groups.
8
3
Hana has 6 balloons. Jana brings 3 more. How many balloons are there in all?
9
4
Look at the shapes. How many triangles? How many circles?
3 triangles and 2 circles
5
What is 4 + 2?
6