Add and Subtract Multi-Digit Numbers

Help Questions

4th Grade Math › Add and Subtract Multi-Digit Numbers

Questions 1 - 10
1

A school library had $$3,508$$ books at the beginning of the year. During the year, they bought $$1,276$$ new books and removed $$847$$ damaged books. At the end of the year, they counted $$3,925$$ books. How many books were lost or stolen during the year?

$$36$$ books were lost or stolen

$$12$$ books were lost or stolen

$$24$$ books were lost or stolen

$$48$$ books were lost or stolen

Explanation

Expected books = $$3,508 + 1,276 - 847 = 3,937$$. Since they counted $$3,925$$ books, the difference is $$3,937 - 3,925 = 12$$ books lost or stolen. Choice B results from an error in the subtraction step. Choice C results from adding the removed books instead of subtracting. Choice D results from calculation errors in multiple steps.

2

Marcus is saving money for a bicycle that costs $$\485$$. He has already saved $$\127$$ and his grandmother gives him $$\95$$. His uncle gives him twice as much as his grandmother gave him. How much more money does Marcus need to buy the bicycle?

$$\95$$ more is needed for the bicycle

$$\73$$ more is needed for the bicycle

$$\168$$ more is needed for the bicycle

$$\263$$ more is needed for the bicycle

Explanation

This is a multi-step word problem that requires you to track money coming in and then calculate how much more is needed. The key is organizing the information and working through each step carefully.

Let's calculate how much money Marcus has total. He starts with $$\127$$ that he already saved. His grandmother gives him $$\95$$, so now he has $$\127 + \95 = \222$$. His uncle gives him twice as much as his grandmother, which means $$2 \times \95 = \190$$. Adding the uncle's money: $$\222 + \190 = \412$$ total.

Since the bicycle costs $$\485$$, Marcus still needs $$\485 - \412 = \73$$ more. This confirms answer choice D is correct.

Looking at the wrong answers: Choice A ($$\95$$) might tempt you if you only counted the grandmother's gift and forgot about the uncle's contribution. Choice B ($$\168$$) could result from forgetting to include Marcus's initial savings of $$\127$$ in your total. Choice C ($$\263$$) appears if you only counted Marcus's original $$\127$$ and ignored both relatives' gifts entirely.

When solving multi-step money problems, write down each amount clearly and add them step by step. Don't try to do all the mental math at once. Also, pay close attention to phrases like "twice as much" – they require an extra calculation that's easy to miss when you're rushing through the problem.

3

The population of Riverside City decreased by $$1,847$$ people last year to $$8,926$$ people. This year, the population increased by $$2,314$$ people. What is the current population of Riverside City?

$$9,393$$ people is the current population

$$11,240$$ people is the current population

$$10,079$$ people is the current population

$$11,087$$ people is the current population

Explanation

When you encounter word problems involving population changes over multiple time periods, you need to track each change step by step, working chronologically through the events.

Let's start with what we know: Riverside City's population decreased by $$1,847$$ people to reach $$8,926$$ people last year. This means we need to find the original population first. If the population decreased by $$1,847$$ to become $$8,926$$, then the original population was $$8,926 + 1,847 = 10,773$$ people.

Now we can find the current population. This year, the population increased by $$2,314$$ people from last year's $$8,926$$. So the current population is $$8,926 + 2,314 = 11,240$$ people, which is answer choice C.

Let's examine why the other answers are incorrect. Answer A ($$10,079$$) likely comes from incorrectly subtracting the increase instead of adding it: $$8,926 - 2,314 = 6,612$$, then making another error. Answer B ($$9,393$$) appears to result from adding only part of the increase or making calculation errors. Answer D ($$11,087$$) is close but represents a computational mistake, possibly switching digits or adding incorrectly.

Remember this strategy for multi-step word problems: identify your starting point, then work through each change in chronological order. Don't try to combine all the operations at once—take it one step at a time to avoid mixing up additions and subtractions.

4

Elena collected $$2,679$$ bottle caps for recycling. She gave $$845$$ to her brother and $$567$$ to her sister. Her cousin then gave her $$429$$ more bottle caps. If Elena needs $$2,000$$ bottle caps for a school project, how many more does she need?

$$1,696$$ more bottle caps does Elena need

$$429$$ more bottle caps does Elena need

$$304$$ more bottle caps does Elena need

$$133$$ more bottle caps does Elena need

Explanation

This is a multi-step word problem that requires you to track Elena's bottle caps as they change through several transactions, then compare her final amount to her goal.

Let's work through Elena's bottle cap journey step by step. She starts with $$2,679$$ bottle caps, then gives away $$845$$ to her brother and $$567$$ to her sister. After giving away bottle caps: $$2,679 - 845 - 567 = 1,267$$ bottle caps remaining. Then her cousin gives her $$429$$ more, so her final amount is: $$1,267 + 429 = 1,696$$ bottle caps. Since Elena needs $$2,000$$ bottle caps for her project, she still needs: $$2,000 - 1,696 = 304$$ more bottle caps.

Choice A ($$1,696$$) represents Elena's current total number of bottle caps, not how many more she needs. This is a common trap when students stop calculating one step too early. Choice C ($$133$$) likely comes from calculation errors in the subtraction steps. Choice D ($$429$$) is simply the number of bottle caps her cousin gave her, which doesn't answer the question being asked.

The correct answer is B: Elena needs $$304$$ more bottle caps.

When solving multi-step word problems, always identify what the question is actually asking for at the end. Write down each step clearly and double-check that your final answer matches the question. Here, the key phrase is "how many more does she need," which requires comparing her current amount to her goal.

5

A toy store received three shipments of toys. The first shipment had $$2,345$$ toys, the second had $$1,789$$ toys, and the third had $$1,056$$ toys. If the store sold $$2,817$$ toys, how many toys are left in the store?

$$2,373$$ toys are left in the store

$$2,473$$ toys are left in the store

$$2,283$$ toys are left in the store

$$3,127$$ toys are left in the store

Explanation

When you see a word problem involving multiple additions and subtractions, break it down into clear steps: first find what came in, then subtract what went out.

Start by adding all three shipments to find the total toys received: $$2,345 + 1,789 + 1,056$$. Let's add step by step: $$2,345 + 1,789 = 4,134$$, then $$4,134 + 1,056 = 5,190$$ total toys received.

Now subtract the toys sold: $$5,190 - 2,817 = 2,373$$ toys remaining. This matches answer choice D.

Let's see why the other answers are wrong. Choice A ($$2,473$$) likely comes from a calculation error when adding the shipments—perhaps mixing up digits or making an arithmetic mistake. Choice B ($$2,283$$) suggests an error in the final subtraction step, possibly subtracting incorrectly or using the wrong total. Choice C ($$3,127$$) is too high and might result from forgetting to subtract the sold toys entirely, or making a major addition error.

The key strategy for multi-step word problems like this is to organize your work clearly: write down what you're finding at each step (total received, then amount remaining), and double-check your arithmetic. Many students rush and make calculation errors, so take time to verify each step. Remember that "left" or "remaining" always means you need to subtract what was used or sold from what you started with.

6

A bakery made $$1,568$$ cookies in the morning and $$1,247$$ cookies in the afternoon. They packaged the cookies into boxes of $$12$$ cookies each and had $$7$$ cookies left over. How many complete boxes did they make?

$$235$$ complete boxes were made by the bakery

$$234$$ complete boxes were made by the bakery

$$228$$ complete boxes were made by the bakery

$$281$$ complete boxes were made by the bakery

Explanation

When you see a problem about packaging items into groups, you're working with division and remainders. The key is understanding that you need to find how many complete groups you can make, not including any leftover items.

First, find the total number of cookies by adding the morning and afternoon amounts: $$1,568 + 1,247 = 2,815$$ cookies total. Since they had $$7$$ cookies left over after packaging, you know that $$2,815 - 7 = 2,808$$ cookies were actually packaged into complete boxes.

Now divide the packaged cookies by the number of cookies per box: $$2,808 ÷ 12 = 234$$ complete boxes. You can verify this: $$234 × 12 = 2,808$$ packaged cookies, plus $$7$$ leftover cookies equals $$2,815$$ total cookies.

Choice A ($$235$$) represents a common error where students might round up when they see a remainder, forgetting that you can't have a complete box with only $$7$$ cookies when you need $$12$$. Choice C ($$281$$) likely comes from incorrectly dividing the total $$2,815$$ by $$10$$ instead of $$12$$, or making an addition error. Choice D ($$228$$) might result from calculation mistakes in either the addition or division steps.

The correct answer is B: $$234$$ complete boxes.

Remember: in division word problems involving "complete" groups, always check if there are remainders mentioned. If items are left over, subtract those first before dividing, since they don't form a complete group.

7

Maya is collecting stickers for a school project. She starts with $$1,247$$ stickers. Her friend gives her $$386$$ more stickers, but then she uses $$529$$ stickers for her project. How many stickers does Maya have left?

$$1,104$$ stickers

$$1,204$$ stickers

$$1,014$$ stickers

$$1,162$$ stickers

Explanation

First, add the stickers Maya received: $$1,247 + 386 = 1,633$$. Then subtract the stickers she used: $$1,633 - 529 = 1,104$$. Choice B results from an error in the first addition ($$1,247 + 386 = 1,633$$, but calculating as $$1,691$$). Choice C results from subtracting before adding. Choice D results from an error in the final subtraction.

8

A farmer harvested $$6,425$$ apples from his orchard. He sold $$2,847$$ apples at the farmers market and $$1,956$$ apples to a local grocery store. He then picked $$834$$ more apples from trees he had missed. How many apples does the farmer have now?

$$2,456$$ apples does the farmer have now

$$1,622$$ apples does the farmer have now

$$3,622$$ apples does the farmer have now

$$2,290$$ apples does the farmer have now

Explanation

This is a multi-step word problem that requires you to track the farmer's apple count as it changes through different events. When solving problems like this, identify each action and whether it increases or decreases the total.

Let's follow the farmer's apples step by step. He starts with $$6,425$$ apples. Then he sells $$2,847$$ apples at the farmers market and $$1,956$$ apples to a grocery store - these are both subtractions. After selling, he has: $$6,425 - 2,847 - 1,956 = 1,622$$ apples remaining.

But the story isn't over! He then picks $$834$$ more apples from trees he missed. This is an addition: $$1,622 + 834 = 2,456$$ apples. So the correct answer is C.

Looking at the wrong answers: Choice A gives $$1,622$$, which is what the farmer had after selling but before picking the additional apples - this stops the calculation too early. Choice B shows $$3,622$$, which likely comes from incorrectly adding one of the sold amounts instead of subtracting it. Choice D gives $$2,290$$, which might result from calculation errors or mixing up the order of operations.

When tackling multi-step word problems, read through once to understand the full situation, then work step by step. Keep track of whether each action adds to or subtracts from your running total. Double-check that you've included all steps mentioned in the problem before selecting your final answer.

9

The attendance at a baseball game was $$4,863$$ people. If $$1,547$$ more people had attended, the stadium would have been completely full. However, $$729$$ people left early during the game. What was the attendance when the game ended?

$$4,681$$ people attended when the game ended

$$4,134$$ people attended when the game ended

$$5,139$$ people attended when the game ended

$$4,863$$ people attended when the game ended

Explanation

The stadium capacity information ($$1,547$$ more for full capacity) is not needed to solve the problem. Simply subtract those who left early: $$4,863 - 729 = 4,134$$. Choice B results from adding instead of subtracting the people who left. Choice C includes the additional people needed for capacity. Choice D ignores that people left early.

10

What is $6,807 + 9,958$?​

15,665

16,665

16,675

16,765

Explanation

This question tests 4th grade fluency with adding and subtracting multi-digit whole numbers using the standard algorithm (CCSS.4.NBT.4). The standard algorithm for addition involves aligning numbers by place value, adding each place starting from the ones, and regrouping (carrying) when the sum in a place is 10 or more. The standard algorithm for subtraction involves aligning numbers by place value, subtracting each place starting from the ones, and regrouping (borrowing) when the top digit is less than the bottom digit. Regrouping means taking 10 from the next left place and adding it to the current place. To add 6,807 and 9,958, align the places and add ones (carries if ≥10), tens (including any carried value), hundreds, and so on, requiring proper regrouping to get the correct sum. Choice B is correct because following the standard algorithm with proper regrouping: ones 7+8=15 (write 5, carry 1), tens 0+5+1=6, hundreds 8+9=17 (write 7, carry 1), thousands 6+9+1=16 (write 6, carry 1), ten thousands 0+0+1=1, giving 16,765. This demonstrates fluent use of the standard algorithm with proper place value alignment and regrouping. Choice A represents forgetting to carry over in the thousands place, which happens when students add 6+9=15 without adding the carried 1. To help students: Use graph paper or place value columns to align digits correctly. For addition, emphasize checking each column—if sum is 10 or more, write the ones digit and carry the tens digit to the next column. For subtraction, check each column—if top digit is less than bottom digit, borrow 10 from the next left column (reducing that column's top digit by 1). Practice borrowing across zeros (like 5,003 - 2,456) by borrowing from the next non-zero place. Have students estimate first (round to nearest thousand) to check if answer is reasonable. Watch for: forgetting to add carried values, subtracting smaller from larger in each column without borrowing, not reducing the borrowed-from digit, and misaligning place values.

Page 1 of 5