Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Place Value Columns: Every four-digit number is made of Thousands (), Hundreds (), Tens (), and Ones (). Imagine a grid where each digit has its own house; the value of a digit depends on which house it lives in. For example, in , the is in the Thousands house.
Base-10 Visual Representations: We can visualize numbers using blocks. A large 'cube' represents , a flat 'square' represents , a 'rod' represents , and a tiny 'unit cube' represents . To show , you would draw large cubes, flats, rods, and unit cube.
Expanded Form: This is writing a number to show the value of each digit as an addition sentence. For the number , the expanded form is . It helps us see exactly how much each part of the number is worth.
Comparing and Ordering: To find which number is bigger, we compare digits starting from the left (Thousands). If the Thousands are the same, we look at the Hundreds, and so on. We use the 'alligator mouth' symbols: (greater than), (less than), and (equal to).
Rounding to the Nearest 1,000: Visualize a number on a hill. If the Hundreds digit is or , the number slides back down to the current thousand. If the Hundreds digit is or , it has enough energy to climb over the peak to the next thousand.
Partitioning: Numbers can be split in different ways, not just by place value. For example, can be partitioned into , or it can be seen as Hundreds or Tens. This is like sharing marbles into different sized bags.
Number Line Placement: On a number line from to , the halfway point is . Visualizing where a number sits (closer to or closer to ) helps in understanding the magnitude and scale of large numbers.
📐Formulae
💡Examples
Problem 1:
Write the number in expanded form and identify the value of the digit .
Solution:
Step 1: Identify the place of each digit. is in the Thousands, is in the Hundreds, is in the Tens, and is in the Ones. Step 2: Write as an addition expression: . Step 3: Determine the specific value of . Since it is in the Hundreds place, .
Explanation:
By breaking the number into its constituent parts, we can see the weight of each digit based on its position.
Problem 2:
Round the number to the nearest thousand and the nearest hundred.
Solution:
Step 1 (Nearest Thousand): Look at the Hundreds digit, which is . Since , we round the Thousands digit up from to . Result: . Step 2 (Nearest Hundred): Look at the Tens digit, which is . Since , the Hundreds digit stays at . Result: .
Explanation:
Rounding depends on the digit to the immediate right of the place value you are rounding to.