Addition Word Problems Up to 100

An addition word problem tells a short story about two amounts being put together, and asks you to find the total. In this lesson, the numbers involved are two-digit numbers, so every sum stays at or below 100. Solving these problems is not just about knowing how to add, it is about turning words into a number sentence you can actually solve.

Before working through story problems, it helps to be comfortable with the basic mechanics of adding two-digit numbers. If you need a refresher on lining up tens and ones, review adding digits up to 100 first, then come back to apply that skill to real situations.

Word problems usually hide clues that tell you addition is the right operation. Watch for phrases such as "in all," "altogether," "combined," "total," "how many now," or "how many in both." These words signal that two groups are being joined into one.

Read the problem again and underline only the numbers you actually need. Some problems include extra information that does not belong in the equation, so it is important to identify which two amounts are actually being combined.

Once you know the numbers and the operation, write a number sentence. For example, "Maria has 47 stickers. She buys 38 more stickers. How many stickers does she have now?" becomes \( 47 + 38 = ? \).

Line the numbers up by place value, add the ones first, then the tens. If the ones add up to 10 or more, regroup one ten into the tens column before adding the tens.

So Maria has \( 85 \) stickers in all. If you would like more practice with the regrouping step itself, the lesson on addition strategies covers several ways to handle carrying between place values.

Before trusting your answer, estimate first. Round \( 47 \) to \( 50 \) and \( 38 \) to \( 40 \). Since \( 50 + 40 = 90 \), an answer near \( 90 \) is reasonable, and \( 85 \) fits that check. Always reread the question and make sure your number answers what was actually asked, not just any sum you calculated.

Some story problems join more than two amounts. For example: "A farmer picked 24 apples on Monday, 19 apples on Tuesday, and 32 apples on Wednesday. How many apples did the farmer pick in all?"

The key words "in all" tell you to add. The equation is \( 24 + 19 + 32 = ? \). Adding two numbers at a time, \( 24 + 19 = 43 \), and \( 43 + 32 = 75 \). The farmer picked \( 75 \) apples in all. Problems with three addends like this one get their own detailed treatment in adding with 3 numbers up to 100.

When you are just starting out, try acting out the story with counters or drawing quick tally marks for smaller parts of a problem, then move to writing the equation directly. Strategies such as using doubles or counting on can make the mental math faster once the equation is set up. If you want to build speed on the addition itself before tackling more word problems, practicing with counting strategies is a great next step.

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