lesson
Updated 1 month ago · 5 views
Imagine you have 243 rocket stickers in an album, and your friend gives you 125 robot stickers. How many stickers do you have altogether?
To find the total, we stack the numbers on top of each other using place value, which is the value of each digit based on where it sits.
📊A clear, colorful base-ten place value diagram comparing 243 and 125 side-by-side and stacked. Three labeled columns: Hundreds (H, green), Tens (T, orange), Ones (O, blue). Under 243: 2 green 100-squares, 4 orange 10-rods, 3 blue 1-cubes. Under 125: 1 green 100-square, 2 orange 10-rods, 5 blue 1-cubes. Clear vertical alignment with column lines. Responsive card layout, max width 350px.
Why do we line up the digits? Because only matching things can be counted together: ones add to ones, tens add to tens, and hundreds add to hundreds.
Ready to solve it? Let's follow the golden rule of addition: always start on the right with the ones column.
Step-by-Step Addition
First, add the ones column: 3 ones+5 ones=8 ones. Write 8 under the ones.
Next, move left to the tens column: 4 tens+2 tens=6 tens. Write 6 under the tens.
Finally, add the hundreds column: 2 hundreds+1 hundred=3 hundreds. Our answer is 368!
📊An interactive or step-by-step animated vertical addition card for 243 + 125 = 368. Shows 3 labeled columns: H (green), T (orange), O (purple). Step 1 highlights 3 + 5 = 8 in the ones place. Step 2 highlights 4 + 2 = 6 in the tens place. Step 3 highlights 2 + 1 = 3 in the hundreds place. The bottom total reads 368 with nice bold digits. Responsive, max width 350px.
What happens if one of the digits is a zero? Does the same rule still work?
Adding with Zero
Zero simply means having nothing in that group. When you add zero to any number, the number stays exactly the same.