Subtracting with Gerbert’s abacus

Slides:

Advertisements

Similar presentations

Multiplying large numbers by splitting

Advertisements

Jeopardy Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy.

Lesson 5-5 Example Example 2 Find 721 ÷ 7. 1.Estimate. 700 ÷ 7 = 100.

Understanding Value of Places

Column Method for Subtraction. Steps to success 1.Put the largest number on top. 2.Place the digits in the correct column. 3.Show the subtraction and.

Long Multiplication What is long multiplication?

Basic Column Subtraction. 1.Write out the numbers that are being subtracted below each other. When subtracting the largest number is always written at.

To the tens, hundreds and thousands

Jeopardy Place Value AdditionSubtractionPlus 10 Money Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy.

Jeopardy People DatesEventsCultureTriviaEconomy.

Place value and ordering

Multiplication methods. Multiplying  Multiplication is mainly taught in three ways - the grid method, Chinese multiplication and traditional column method.

Jeopardy Reduce Fraction Division Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy What’s the rule? Place Value Multiply.

Multiplication -2D by 2D Kids Learning is Fun

$100 $200 $300 $400 $100 $200 $300 $400 $300 $200 $100 Estimate with pictures Round to nearest hundred Round to nearest thousand Add / subtract & estimate.

Lesson 3-6 Example Example 2 Find the difference 572 and 286. Use expanded form. 1.Write the first number in expanded form

Step-Book With Professor Assessor ©

CS101 Learning Binary Learning Binary What do you think when you see One hundred and one What does a computer think when it sees 101? 5.

Rounding of Numbers Up to Hundred Millions

Step-by-Step Everyday Mathematics Review Partial Sums AdditionPartial Sums Addition Trade-First SubtractionTrade-First Subtraction Partial Products MultiplicationPartial.

Subtracting Polynomials

Adding and subtracting decimal numbers Written methods.

An alternative subtraction algorithm. In order to subtract, the top number must be larger than the bottom number To make the top number.

SUBTRACTION: 3-digit number from a 3-digit number: regrouping from 1's & 10's columns. Subtract the ones first. (subtrahend) (minuend)Check to make sure.

$100 $200 $300 $400 $100 $200 $300 $400 $300 $200 $100 Multiply by 1 digit numbers Multiply & estimate results Multiply by 2 digit numbers Multiply.

Using multiplication and written methods ©

Steps of Addition Move your mouse over each step to see the directions.

Today we will be learning: to count on in ones or tens to count back in ones or tens to split two-digit numbers into tens and units to make them easier.

Adding Two and Three Digit Numbers

Estimation and Computation By: Your Name (First, Last) Section: O-

Everyday Mathematics Partial-Differences Subtraction.

Addition and Subtraction 29 Addition and Subtraction Algorithms 2 ones plus 9 ones equal 11 ones. 11 is 1 ten and 1 one. Record the 1 one in the ones column.

$200 $400 $600 $800 $1000 $200 $400 $600 $800 $1000 $200 $400 $600 $800 $1000 $200 $400 $600 $800 $1000 $200 $400 $600 $800 $1000 $200.

Subtraction Elizabeth Johnston Nail Abacus 57-34= Students place 5 washers on the tens nail Students place 7 washers on the ones nail Students are then.

Subtraction with Borrowing By Mrs. Cupples So let’s say that we start with the following math problem…

2 digit addition no regrouping drawing Dienes recap Year 2

2 Digit by 2 Digit Multiplication

4 3 9 H T U What is the most significant figure in

Comparing Numbers.

Relationship of Numbers in the Place Value System

(The largest number has 3 digits so there will be 3 parts.)

Remember hundreds, tens and units!

CS101 Learning Binary Learning Binary.

Column subtraction Yesterday we learnt to subtract vertically in columns Can you remember the main things to remember? ©

Understanding Value of Places

Understanding Value of Places

Expanded Notation , , , , , , Name: _________________________________

Partial products By: Elias and Adam.

Subtracting Whole Numbers

Hundred Dollar Questions

Column subtraction Start on the right-hand side

What Number Am I?.

Three Digit Subtraction

Subtracting 10 Dice Roll Directions:

Subtracting Integers Sec 2.3 pg

Which is the largest number?

How to?..... Column addition By Lily Fry.

Column subtraction So far we have subtracted horizontally

Good Morning ! Here’s your warm up..

Adding and Subtracting

Comparing Numbers.

Column subtraction Start on the right-hand side

Strategies for solving 3-digit subtraction problems.

Presentation transcript:

Subtracting with Gerbert’s abacus

Subtracting on an abacus 9 1 7 - 6 4 2

Subtracting on an abacus Start with the hundreds: 9 – 6 = 3

Subtracting on an abacus Now go to the tens: We have 1 – 4.

Subtracting on an abacus Since 4 is larger than 1, we go to the hundreds column and split the 3 into 2 and 1.

Subtracting on an abacus Now we have eleven tens, so we can subtract 4 from them to get 7 tens.

Subtracting on an abacus Now we have eleven tens, so we can subtract 4 from them to get 7 tens.

Subtracting on an abacus Finally, we go to the ones column and subtract 2 from 7.

Subtracting on an abacus The final answer is 275.