Mastering Addition with Open Number Lines

What is an open number line?

• A concept in geometry for measuring angles

• A mathematical tool used only for subtraction

• A number line with predefined numbers and markers

• A number line with no numbers or markers, added as needed

What is the starting number in the addition equation demonstrated?

• 256

• 100

• 137

• 386

Why is an open number line useful for addition?

• It is only useful for subtraction

• It visually represents mathematical thinking based on place value

• It simplifies complex equations

• It automatically calculates the sum

How much is 256 plus 100?

• 256

• 100

• 356

• 456

What is the result of adding three tens to 356?

• 376

• 396

• 366

• 386

How can adding multiples of ten become more efficient?

• By adding each ten separately

• By skipping the addition

• By adding all tens at once

• By subtracting instead

What landmark number is reached by adding four to 386?

• 393

• 386

• 400

• 390

What strategy is used to add the ones place value?

• Adding all at once

• Decomposing into smaller numbers

• Ignoring the ones place

• Multiplying instead of adding

What is the final sum of 256 plus 137?

• 386

• 400

• 393

• 390