Cross Products I am learning to multiply multi-digit whole numbers. 37 X 28 = ? Before starting this lesson make sure you are confident with the lesson.

Slides:

Advertisements

Similar presentations

Let’s Do Algebra Tiles.

Advertisements

Fractional Blocks I am learning to use patterns to find fractions of shapes and sets. Half of a square. Half of a half a square.

Don’t Subtract Add I am learning that problems like 34 + ? = 51 and 51 – 34 = ? have the same answer. e.g = 51 and 51 – 34 = 17.

Decimats I am learning to identify equivalent fractions and to name fractions as decimals. Equivalent means equal or the same.

Comparing Apples with Apples I am learning to add and subtract fractions with unlike denominators. + = ?- = ? Before starting this lesson you need to be.

Comparisons I am learning to add and subtract using comparisons of sets without counting down or counting up. Looking at one group and another group at.

Brmmm! I am learning to solve problems in which a fraction measures another fraction.

Seed Packets I am learning to solve simple ratio problems by repeated copying. Compare one amount to another. e.g. a packet of sweets contains 2 blue sweets.

Combining proportions I am learning to combine proportions and work out what parts the total is made up of.

Hills and Dales I am learning to add and subtract integers (positive and negative numbers). -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5.

How many ten-dollar notes I am learning how many tens there are in numbers less than 1000.

Big Number Multiplication IntroductionQuestionsDirections.

Multiplication and Division problems use the same numbers. These groups of numbers are called number or fact families x ÷ They all fit together.

Long Multiplication What is long multiplication?

What is Numeracy? Numeracy covers the following skills: Addition and Subtraction Multiplication and Division Fractions, Decimals and Percentages.

Adding with decimal fractions. I am learning to add with 1 decimal place fractions. Questions like = ?

Feeding Pets I am learning to find fractions between two other fractions. 0 1 And many more. e.g.

Multiplication Smorgasbord I am learning to solve multiplication problems using a variety of mental strategies. Work it out in your head At a smorgasbord.

Introducing decimal fraction place value. I am learning how tenths arise out of division. e.g. 3 ÷ 2 = 1 whole and 5 tenths.

Paper Power 1 (Multiplication) I am learning to work out multiplication problems using written working forms. 24 x

Powerful Numbers I am learning to solve multiplication problems with powers (exponents). e.g. 2 2 or 2 3.

Problems like 73 – 19 = ….. I am learning to solve division problems like = … by first subtracting a tidy number and then adding on a small number.

Trains I am learning to find where fractions live amongst whole numbers., etc. 2, 3, 4, etc. Improper fraction: The numerator is larger than the denominator.

Equal Additions I am learning to solve subtraction problems by equal additions that turn one of the numbers into a tidy number. Numbers like 10, 20, 30,

Cut and Paste I am learning to solve multiplication problems using doubling and halving, thirding and trebling, and other proportional adjustments. 2 X.

Fun with fives I am learning to work out my times six, seven, and eight tables from my times five tables.

Rates of Change I am learning to solve rate problems.

Remainders I am learning to solve division problems that have remainders. An amount left over that can’t be shared out evenly.

STEPS FOR MULTIPLYING A 2-DIGIT NUMBER BY ANOTHER 2-DIGIT NUMBER With Partial Products.

Adding in Parts I am learning to add by splitting numbers into parts. Example : 8 can be split into or 2 and 6 or 3 and 5 or 4 and 4 1 and 7.

Multiplying tens I am learning to multiply tens, hundreds, thousands, and other tens numbers. 10, 20, , 200, , 2000, 3000.

Extending Mixing Colours I am learning to solve difficult ratio problems. Do not start this lesson unless you have an excellent understanding of Mixing.

Subtracting tenths. I am learning to subtract with 1 decimal place fractions. Questions like = ?

Lesson 10: I can multiply decimal fractions with tenths by multi-digit whole numbers using place value understanding to record partial products. 5th Grade.

Multiplication with tenths. I am learning to multiply a whole number by a decimal fraction. Questions like 4 X 1.2 = ?

Multiple ways to add and subtract I am learning to use multiplication and division to solve addition and subtraction problems.

Jumping the number line I am learning to jump through a tidy number on a number line to solve problems like 17 + …. = 91 Numbers like 10, 20, 30, 40 etc.

Hot Shots. FDcghttp:// FDcg.

Large Numbers Roll Over I am learning how a number rolls over when 10 of any unit occur in addition, and how the number rolls back when 10 of any unit.

Solving Equations Inverse operations. INVERSE = Opposite If I am solving an equation using inverses operations, I am solving it using opposite signs.

Problems like 37 + … = 79 I am learning to add mentally the ones and tens separately when appropriate. 84 TensOnes.

Dollars and Bills I am learning to add integers (positive and negative numbers). e.g. -5 e.g. +5.

Problems like … + 29 = 81 I am learning to reverse problems like □ + 29 = 81 to 29 + □ = 81 and then use an appropriate mental method to solve the problem.

The decimal fraction point. I am learning to use the shorthand for tenths. e.g. 0.1, 0.2, 0.3.

When one number is near a hundred I am learning to solve some addition and subtraction problems by adjusting one number to the nearest hundred. or 301.

Estimation as a check I am learning to check any addition and subtraction problem I cannot solve mentally by estimating the answer. You may have used a.

Problems like 67 - … = 34 I am learning to solve problems like 67 – ? = 34 by solving 34 + ? = 67 or by finding 67 – 34.

Decomposition I am learning a standard method of doing a subtraction problem on paper when the numbers are too difficult to find the answer mentally. In.

The Royal Cooking Lesson I am learning to solve division problems by changing them to simpler problems that have the same answer.

Problems like 23 + …….. = 71 I am learning to solve problems like 13 + ……. = 91 by jumping up by a tidy number on a number line, then jumping back a small.

What is 10-5? Correct! Click on the picture below to answer another question!

RELATE ARRAYS TO TAPE DIAGRAMS TO MODEL THE COMMUTATIVE PROPERTY OF MULTIPLICATION. Module 1 Lesson 15.

Long Jumps I am learning to solve division problems using the repeated addition and multiplication facts I know X 3.

A Balancing Act I am learning that the answer on the left of the equals sign is the same as the answer on the right of the equals sign. = means they balance.

Standard written form for addition I am learning a standard method of doing an addition problem on paper when the numbers are too difficult to find the.

Multiplying Whole Numbers

Homework Correction Pg 75 Ex 6a 1-16

Multiplication Grids Multiplying a 2 digit number by a 1 digit number.

Proportional Packets I am learning to solve division problems using how many times one number will go into another. e.g. 36 ÷ 6 = 6 so 36 ÷

Multiplication Grids Multiplying a 2 digit number by a 1 digit number.

Extending Mixing Colours

Division with tenths. I am learning to do simple division by a whole number with tenths in the answer. Questions like 4.2 ÷ 7 = ?

Mixing colours I am learning to compare ratios and proportions. 3:7.

Nines and threes I am learning to decide if a number is divisible by nine or three. Can the number be shared evenly between 9 or 3.

Three or more at a time. I am learning to look at the addition and subtraction of three or more numbers to calculate easy combinations first. e.g. 3 +

Powerful Numbers I am learning to solve multiplication problems with powers (exponents). e.g. 22 or 23.

Turn Abouts I am learning to change the order of the numbers to make multiplication easier. e.g. 8 X 2 = or 2 X 8 =

Proportional Packets I am learning to solve division problems using how many times one number will go into another. e.g. 36 ÷ 6 = 6 so 36 ÷

Multiplication Smorgasbord

Comparing Apples with Apples

Presentation transcript:

Cross Products I am learning to multiply multi-digit whole numbers. 37 X 28 = ? Before starting this lesson make sure you are confident with the lesson Paper Power (for multiplication).

There are 17 rows with 32 counters in each row. How many counters are there in total? 17 X 32= ? Imagine this displayed as a rectangle. Now split the 32 and 17 into a tidy number and an amount left over You can see there are 4 rectangles. By finding the area of each of these we can work out the area of the whole rectangle and the answer to our question. 30 X 10 = 3002 X 10 = 202 X 7 = 1430 X 7 = 210 Add all the areas together = 544 So 17 X 32 = 544

There are 27 rows with 47 counters in each row. How many counters are there in total? 27 X 47= ? Imagine this displayed as a rectangle. Now split the 27 and 47 into a tidy number and an amount left over You can see there are 4 rectangles. By finding the area of each of these we can work out the area of the whole rectangle and the answer to our question. 40 X 20 = 8007 X 20 = 1407 X 7 = 4940 X 7 = 280 Add all the areas together = 1,269 So 27 X 47 = 1,269

Now let’s try an example without the diagram. 18 X 43 = ? Firstly split the numbers into a tidy number and an amount left over. (10 + 8) X (40 + 3) = ? You saw from our earlier diagrams that every number on the left hand side of the multiplication sign must be multiplied by every number on the right hand side of this sign. 10 X 40 = X 3 = 308 X 40 = 3208 X 3 = 24 Now add the amounts together = X 43 = 774

Below is an example of how I like to set out my working for these types of question. 32 X 52 = ? (30 + 2) X (50 + 2) = ?Step 1: I expand the number Step 2: I draw in lines showing all the numbers I must multiply together. I always do 2 above and 2 below so I don’t mix any of my lines up. As I draw in the lines I record each part of the multiplication. (30 X 50) +(30 X 2) + (2 X 50) +(2 X 2) Step 3: Below this I record the answers = 1,664 So 32 X 52 = 1,664

Use this strategy (cross products) to work out answers to the questions below. 1) 25 X 33 = ? 2) 17 X 42 = ? 3) 32 X 45 = ? 4) 18 X 23 = ? 5) 26 X 23 = ? Need some more practise? Try Pg45 & 46 of Teacher Tools Multiplication and Division Book Numeracy resourcesNumeracy resources Click again when you have worked out all your answers ,