31
Column addition
Textbook: Part 1, lesson 30, pp. 64–65
GoalLearn column addition of two-digit numbers with carrying.
New words
column · ustuncarrying · xonadan o‘tishsum · yig‘indito memorise · yod olish
Explanation
In a column we write ones under ones and tens under tens. We add the ones: if the total is more than 10 we write the ones and put the 1 ten above the tens. Then we add the tens (and that extra 1).
Worked examples
48 + 29: 8 + 9 = 17, write 7 and carry 1 ten. Tens: 4 + 2 + 1 = 7. Answer 77.
36 + 36: 6 + 6 = 12, write 2 and carry 1; 3 + 3 + 1 = 7. Answer 72.
Class activity
“The travelling ten”: a column is drawn on the board. Children take turns carrying a “ten” card from the ones column to the tens column and say why.
Practice
1
18 + 16 = ?
34
2
37 + 18 = ?
55
3
28 + 54 = ?
82
4
Dilshod collected 27 stamps and Aziz collected 36. How many stamps in all?
63