Subtraction for second grade

What is Subtraction?

Subtraction is taking one number away from another. It helps us find out how much is left. The symbol for subtraction is "-".

For example:

$$ 5 - 2 = 3 $$

This means if you have 5 apples and you take away 2, you will have 3 apples left.

Understanding Subtraction with Objects

Let's use blocks to understand subtraction:

1. Start with 7 blocks.
2. Take away 3 blocks.
3. Count how many blocks are left.

$$ 7 - 3 = 4 $$

You have 4 blocks left!

Subtraction on a Number Line

We can use a number line to subtract. Here’s how:

1. Start at the first number.
2. Move left for each number you subtract.

Example:

$$ 9 - 4 $$

1. Start at 9.
2. Move 4 steps left.
3. Land on 5.

So,

$$ 9 - 4 = 5 $$

Subtracting Without Regrouping (Simple Subtraction)

If the top number is bigger than the bottom number, we can subtract normally.

Example:

$$ 24 - 12 $$

• Subtract the ones place: $4-2=2$
• Subtract the tens place: $2-1=1$

Answer:

$$ 24 - 12 = 12 $$

Subtracting With Regrouping (Borrowing)

Sometimes, the top number is smaller than the bottom number, so we need to borrow from the next column.

Example:

$$ 32 - 17 $$

1. Look at the ones place: $2-7$ (we can't do this!)
2. Borrow 1 from the tens place: The 3 becomes a 2, and the 2 in ones place becomes 12.
3. Now, subtract: $12-7=5$
4. Subtract the tens place: $2-1=1$

Answer:

$$ 32 - 17 = 15 $$

Word Problems

1. Sarah has 8 candies. She eats 3. How many does she have left?

   $$ 8 - 3 = 5 $$

2. John has 25 marbles. He gives 9 to his friend. How many does he have now?

   $$ 25 - 9 = 16 $$

Practice Problems

Solve these subtraction problems:

1. $$ 15 - 7 = $$
2. $$ 42 - 18 = $$
3. $$ 60 - 35 = $$
4. $$ 83 - 29 = $$
5. $$ 51 - 26 = $$

Subtraction Test

Part 1: Basic Subtraction

Solve the following problems.

1. $$ 9 - 4 = $$
2. $$ 17 - 8 = $$
3. $$ 24 - 9 = $$
4. $$ 38 - 14 = $$
5. $$ 55 - 27 = $$

Part 2: Subtraction with Regrouping

Solve the following problems.

6. $$ 41 - 16 = $$
7. $$ 63 - 28 = $$
8. $$ 75 - 39 = $$
9. $$ 92 - 57 = $$
10. $$ 81 - 46 = $$

Part 3: Word Problems

Solve these problems by showing your work.

11. Emma has 45 stickers. She gives 19 to her friend. How many stickers does she have left?

12. A store had 82 oranges. They sold 36. How many are left?

13. There were 60 students on a bus. 24 got off at a stop. How many are still on the bus?

14. Jake has 93 toy cars. He lost 48 of them. How many does he have now?

15. There are 72 books on a shelf. 25 are taken away. How many remain?