Addition Word Problems Up to 1000

An addition word problem describes a real-life situation in sentences instead of a ready-made equation. To solve it, a student must read the story carefully, decide that the parts need to be combined, and then add numbers that can be as large as 1000. These problems build on basic addition skills like adding with digits up to 1000 and addition with tens and ones, but the extra step is turning words into a math sentence.

For example: "A library has 342 fiction books and 256 non-fiction books. How many books does the library have in all?" The words "in all" tell us to add: \( 342 + 256 = 598 \). The library has 598 books.

Certain words and phrases almost always mean the story wants an addition, not a subtraction or another operation. Recognizing them quickly makes it much easier to set up the correct equation.

• in all
• total or altogether
• combined
• sum
• how many are there now (after items are added or joined)

Use the same reliable routine every time to avoid missing information or misreading the question.

1. Read the problem twice. The first time to understand the situation, the second time to pull out the numbers.
2. Underline the question. Know exactly what value is being asked for.
3. Write a number sentence. Turn the story into an equation such as \( a + b = ? \).
4. Solve using place value. Line up hundreds, tens, and ones, and regroup when a column adds to 10 or more.
5. Check the answer. Ask if the sum is a reasonable size for the story, or use estimation to double-check.

A school had 214 students in Grade 3 and 352 students in Grade 4. How many students are in Grades 3 and 4 combined?

Number sentence: \( 214 + 352 \)

Add the ones: \( 4 + 2 = 6 \). Add the tens: \( 1 + 5 = 6 \). Add the hundreds: \( 2 + 3 = 5 \).

So \( 214 + 352 = 566 \). There are 566 students in Grades 3 and 4 combined.

A farmer picked 486 apples on Monday and 275 apples on Tuesday. How many apples did the farmer pick in total?

Number sentence: \( 486 + 275 \)

Ones: \( 6 + 5 = 11 \), write 1 and regroup 1 ten. Tens: \( 8 + 7 + 1 = 16 \), write 6 and regroup 1 hundred. Hundreds: \( 4 + 2 + 1 = 7 \).

So \( 486 + 275 = 761 \). The farmer picked 761 apples in total. This kind of carrying is the same skill practiced in Adding with Digits Up to 1000.

A bar model helps show how two known parts join to make a whole, which is especially useful when a story has more than two numbers to combine.

The two smaller boxes on top represent the two parts given in the story, and the long box on the bottom represents the whole, or the total, that the question is asking for.

Before or after solving, it helps to round each number to the nearest hundred and add the rounded values. For 486 and 275, rounding gives 500 and 300, so the estimate is \( 500 + 300 = 800 \). Since 761 is close to 800, the exact answer looks reasonable. This estimation check is explored further in Addition using Estimation.

• Adding the wrong numbers because the question asks for one specific value, not every number mentioned in the story.
• Forgetting to regroup when a column's sum reaches 10 or more.
• Misaligning place value columns when the two numbers have a different number of digits.
• Skipping the final check, which can let unreasonable answers slip through unnoticed.

Related lessons

• Math 3