The equation 30 − _ = 27 can be solved by ___ to find the missing number.

Subtracting 27 from 30 to find that the missing number is 3.

True or False: The operation required to solve 650 + _ = 1000 is addition.

False. The operation required is subtraction.

In the equation 10 _ 2 = 20, the missing operation is ___.

Multiplication.

What method can be used to find the missing number in the equation 3 _ = 15?

Recognizing that 3 multiplied by 5 equals 15 allows us to determine that the missing number is 5.

What is the result of 1000 - 650?

350

True or False: To compose a whole number, you must split it into its place value components.

False, composing a whole number means putting together parts to form it.

When regrouping, what is the primary purpose during addition or subtraction?

To reorganize numbers to facilitate calculation.

In the expression 300 + 450, what is the sum?

750

What is the result of 235 + 174 using the written method for addition?

459 − 318 equals ___ when using the written method for subtraction.

True or False: The estimation of 424 − 179 is 200.

False. The correct estimation is 400 − 200 = 200.

When decomposing 424 for subtraction, it can be represented as ___ + ___ + ___.

300 + 110 + 14.

What is the result of adding two odd numbers?

The result of adding two odd numbers is always even.

An example of regrouping in subtraction is ___ when subtracting 235 - 174.

Borrowing from the next column when the top digit is smaller than the bottom digit.

Fill in the blank: The difference between 235 and 174 is ___.

61

True or False: The sum of an even number and an odd number is always even.

False; the sum of an even number and an odd number is always odd.

Adding three odd numbers always results in ___ number.

An odd

True or False: A number is considered even if it leaves a remainder of 1 when divided by 2.

False; an even number leaves no remainder when divided by 2.

What is a counter-example in mathematics?

An example that disproves a general statement or claim.

The sum of an even number and an odd number is always ___ number.

An odd