Hundreds Tens And Units Homework Hotline
Practice subtracting numbers within 1000 with carry at the tens place. While subtracting numbers using place value concepts, students subtract ones from ones, tens from tens and hundreds from hundreds. In this method, sometimes it is necessary to break up hundreds into tens and break up tens as ones.
For example, the subtraction 353 - 164 can be viewed as:
3 hundreds 5 tens 3 ones
- 1 hundred 6 tens 4 ones
We can rewrite 3 hundreds 5 tens and 3 ones in 353 in the following way:
Break up a hundred into tens
2 hundreds 15 tens 3 ones
Break up a ten and ones
2 hundreds 14 tens 13 ones
which makes it straight forward to subtract, as shown below:
2 hundreds 14 tens 13 ones
- 1 hundred 6 tens 4 ones
1 hundred 8 tens 9 ones
Subtract by Breaking up Tens and Hundreds Worksheet focuses on problems with such situations, where it is necessary to break up hundreds as tens and tens as ones. This concept is the precursor to the concept of carry in the standard algorithm.
Common Core Alignment
2.NBT.7Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
Ones, Tens, Hundreds:
A Place-Value Game
Subjects
Mathematics
--Arithmetic
Grade
3-5
6-8
Brief Description
By the process of elimination, students figure out the secret 3-digit number.
Objectives
Students will use their knowledge of place value to ask questions that will help them figure out a secret 3-digit number.
Keywords
3-digit number, place value, Ones, Tens, Hundreds
Materials Needed
- pencil and paper
Lesson Plan
This game will help reinforce students understanding of the Ones, Tens, and Hundreds positions in three-digit numbers.
Before playing, refresh students knowledge of the positions of the Ones, Tens, and Hundreds columns. You might draw a representation of the columns and their positions on the board or a sheet of chart paper:
Hundreds Tens Ones
Then provide a series of numbers and ask random questions such as
- What number is in the Tens column in the number 526? (2)
- In which column is the 4 in the number 324? (It is in the Ones column.)
- In the number 479, in which column in the 4? (It is in the Hundreds column.)
- Which number is in the Ones column in the number 611? (1)
Next, write a 3-digit number on a card or a small slip of paper. Keep the number secret from your students. Then invite them to ask yes or no questions about the digits and their positions in the number that will help them figure out what the number is. For example, if you write the secret number 467, students might ask questions such as
- Is the number an even number? (no)
- Is the number in the Tens column between 2 and 6? (yes)
- Is the number in the Hundreds column less than 6? (yes)
- Is the number in the Tens column an odd number? (no)
- Is the number in the Ones column greater than 5? (yes)
- Is the number in the Hundreds column greater than 4? (no)
Go around the room and give each student an opportunity to ask a yes or no question that will help them pinpoint the digits that appear in the Ones, Tens, and Hundreds columns of the secret number. After each student asks her/his question, s/he is entitled to guess the secret number based on the information at hand.
Students might keep track of the possibilities by creating a chart that looks something like this one:
Hundreds | Tens | Ones |
0 1 2 3 4 5 6 7 8 9 | 0 1 2 3 4 5 6 7 8 9 | 0 1 2 3 4 5 6 7 8 9 |
Students might draw an X through each number as their questions remove it from possibility.
So far we know that
- The number in the Hundreds column is not greater than 4, but it is less than 6; that means it cant be 5. It must be 1, 2, 3, or 4..
- The number in the Tens column is an even number between 2 and 6; that means the number in the Tens column must be either 2, 4, or 6.
- The number in the Ones column is an odd number (based on the answer to the first question above) that is greater than 5; that means the number in the Ones column must be either 7 or 9.
With the knowledge above, the questioning continues
- Is the number in the Hundreds column an even number? (yes, so we can eliminate 1 and 3 from the possibilities; it must be 2 or 4)
- Is the number in the Hundreds column less than 3? (no, so we know it must be 4)
- Is the number in the Tens column less than 3? (no, so we know it must be 4 or 6)
- Is the number in the Tens column between 5 and 7? (yes, so we know it must be 6)
- Is the number in the Ones column more than 8? (no, so we know it must 7)
By the process of elimination, we now know the secret three-digit number must be 467.
When the rules of the game and the questioning techniques are clear to your students, you might give a student the opportunity to write down the secret number and respond to classmates questions about the digits that appear in the numbers Ones, Tens, and Hundreds columns.
Assessment
Who was the first student to figure out the secret 3-digit number?
Lesson Plan Source
EducationWorld.com
Submitted By
Gary Hopkins
National Standards
MATHEMATICS: Number and Operations
GRADES Pre-K - 2
NM-NUM.PK-2.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
GRADES 3 - 5
NM-NUM.3-5.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
GRADES 6 - 8
NM-NUM.6-8.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
GRADES 9 - 12
NM-NUM.9-12.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
MATHEMATICS: Problem Solving
GRADES Pre-K - 12
NM-PROB.PK-12.1 Build New Mathematical Knowledge Through Problem Solving
NM-PROB.PK-12.2 Solve Problems That Arise in Mathematics and in Other Contexts
NM-PROB.PK-12.3 Apply and Adapt a Variety of Appropriate Strategies to Solve Problems
NM-PROB.PK-12.4 Monitor and Reflect on the Process of Mathematical Problem Solving
MATHEMATICS: Communications
GRADES Pre-K - 12
NM-COMM.PK-12.1 Organize and Consolidate Their Mathematical Thinking Through Communication
NM-COMM.PK-12.2 Communicate Their Mathematical Thinking Coherently and Clearly to Peers, Teachers, and Others
NM-COMM.PK-12.3 Analyze and Evaluate the Mathematical Thinking and Strategies of Others
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08/21/2010
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