1
Fill the ten first
Joyful Mathematics: Chapter 6
GoalAdd two numbers that go over 10 by making a ten first.
New words
make ten · fill a ten-frame to 10the rest · what is left over after tenteen number · a number from 11 to 19
Explanation
A fruit seller has 9 peaches in one tray and 5 peaches in another tray. Look at the two ten-frames. Move 1 dot to fill the first frame to 10. 4 dots are left over. 10 and 4 make 14. So 9 + 5 = 14.
Worked examples
8 + 4 = 12. 8 and 2 more make 10. 2 more are left over. 10 and 2 make 12.
6 + 7 = 13. The tray has 6 peaches and the box has 7 peaches.
9 + 7 = 16. 9 and 1 make 10. 6 more are left. 10 and 6 make 16.
Class activity
Ten squares. Draw 10 squares in a row on paper. Put 9 stones in the squares. Add 6 more stones. Fill the squares to 10 first. Put the rest outside the squares. Count: 10 and 5 make 15. Try 8 + 7 and 7 + 6 too.
Practice
1
How many dots altogether?
14.
2
How many flowers altogether?
15.
3
What is 9 + 2?
11.
4
Harpreet has 7 marbles. Joseph has 6 marbles. How many marbles altogether?
13.
5
What is 10 + 7?
17.