A focused Grade 4 learning session for Adding and Subtracting Multi-Digit Whole Numbers using visual models, worked examples, strategy guidance, and a short mastery check.
Student goal: I can accurately add and subtract multi-digit whole numbers.
Adding and Subtracting Multi-Digit Whole Numbers means using place value, operations, and equations to reason accurately with numbers.
Question: This place-value chart shows 5,234. If we add 3,456, what digit appears in the hundreds place of the sum?
Why it works: Add: \(5{,}234+3{,}456=8{,}690\). In the hundreds place: \(2+4=6\). The hundreds digit is \(\mathbf{6}\).
Answer: 6
Question: What is the sum \(2{,}347 + 3{,}285\)?
Answer: \(5{,}632\)
Question: Marcus has $6,200. He spends $2,345. How much money does he have left?
Answer: $3{,}855
Question: Noah's school library has 15,678 books. The library receives 5,432 new books. How many books does the library have now?
Why it works: The library receives more books, so we add. \(15{,}678+5{,}432=\mathbf{21{,}110}\) books total.
Answer: \(21{,}110\) books
Adding and Subtracting Multi-Digit Whole Numbers becomes easier when students connect the question to a model, use clear steps, and explain why the answer fits.
Understand the model before choosing the operation.
Use scratch paper. The explanation matters more than simply seeing whether the choice is correct.
What is \(8{,}432-3{,}657\)?
Answer D: \(4{,}775\)
Subtract column by column, regrouping as needed. Starting from the ones: we need to regroup the tens and higher places to complete the subtraction. The answer is \(\mathbf{4{,}775}\).
Add: \(5{,}234 + 2{,}145 =\)?
Answer D: \(7{,}379\)
Add from right to left: ones \(4+5=9\), tens \(3+4=7\), hundreds \(2+1=3\), thousands \(5+2=7\). The sum is \(\mathbf{7{,}379}\).
What is \(9{,}000 - 4{,}256\)?
Answer A: \(4{,}744\)
Since we're subtracting from \(9{,}000\), we must regroup across the zeros to subtract in each place. The answer is \(\mathbf{4{,}744}\).
Subtract: \(6{,}320 - 1{,}485 =\)?
Answer A: \(4{,}835\)
Start in the ones place: \(0 < 5\), so regroup one ten as \(10\) ones. Then subtract from right to left carefully. The answer is \(\mathbf{4{,}835}\).
Add: \(3{,}456 + 4{,}567 =\)?
Answer D: \(8{,}023\)
Add from right to left: ones give \(13\) (write \(3\), carry \(1\)), tens give \(12\) (write \(2\), carry \(1\)), hundreds give \(10\) (write \(0\), carry \(1\)), thousands give \(8\). The sum is \(\mathbf{8{,}023}\).
What is \(10{,}000 - 5{,}678\)?
Answer A: \(4{,}322\)
Subtracting from \(10{,}000\) requires careful regrouping across all the zeros. The answer is \(\mathbf{4{,}322}\).
Add: \(7{,}285 + 1{,}514 =\)?
Answer A: \(8{,}799\)
Add by place value: ones \(5+4=9\), tens \(8+1=9\), hundreds \(2+5=7\), thousands \(7+1=8\). The sum is \(\mathbf{8{,}799}\).
Subtract: \(7{,}104 - 2{,}356 =\)?
Answer A: \(4{,}748\)
In the ones place, \(4 < 6\), so we must regroup. The tens place is zero, so regroup from hundreds. Then subtract carefully. The answer is \(\mathbf{4{,}748}\).
Add: \(12{,}345 + 23{,}456 =\)?
Answer D: \(35{,}801\)
Add from ones: \(5+6=11\) (write \(1\), carry \(1\)), \(4+5+1=10\) (write \(0\), carry \(1\)), \(3+4+1=8\), \(2+3=5\), \(1+2=3\). The sum is \(\mathbf{35{,}801}\).
What is \(50{,}000 - 23{,}456\)?
Answer A: \(26{,}544\)
Subtract from \(50{,}000\) using regrouping. The answer is \(\mathbf{26{,}544}\).
Ava has 8,234 stickers. She gives 2,456 stickers to her friend. How many stickers does Ava have left?
Answer A: \(5{,}778\)
This word problem asks us to find how many are left, so we subtract. \(8{,}234-2{,}456=\mathbf{5{,}778}\) stickers.
