# Grade 3 Maths (IMO) : Division

Let’s talk about what division really is — it is repeated subtraction; much the way multiplication is repeated addition.

Let’s say I have the basic problem 16 ÷  4.  I could start with 16 and then subtract 4, subtract another 4, another 4, and another 4 until I run out and reach zero.  I would have to do this 4 times. If I had 16 cookies that I wanted to share equally among 4 friends, I could do the “one for you, one for you, one for you, and one for you” process and still end up with 4 cookies for each.

But what about 375 ÷ 50? If I don’t know how to divide by double digit numbers, the repeated subtraction process might actually be a good choice . . . at least showing some number sense to know that 375 divided by 50 means “How many 50’s in 375?” I know if I subtract 50 six times, I still have 75 left. I can subtract another 50 and I have 25 left over. So 375 ÷ 50 = 7 with a remainder of 25.

### Dividing using the distributive law

 Division Possible Split Calculation Answer 69 ÷ 3 60 + 9 (60 ÷ 3) = 20 (9 ÷ 3)  = 3 20 + 3 = 23 391 ÷ 3 390 + 1 (390 ÷ 3) = 130 (1 ÷ 3) = cannot be divided 130 with Remainder 1

## Long Division

Before a child is ready to learn long division, he/she has to know: Continue reading

# Grade 3 Maths (IMO) : Number sense

## Place value and Face value

Face value of a digit  is the digit itself whereas Place value can be termed as the location of the digit in the numeral.

The value of a place in the place value chart is 10 times the value of the place just to its right.

# Grade 3 Maths (IMO) : Multiplication Strategies

A quick look at the grade 2 lesson on introduction to multiplication

Taming the tables &#8211; Tips to introduce multiplication

### While multiplying always remember :

An even number  x an even number = an even number

An odd number x an even number = an even number

An odd number x an odd number = an odd number

### Distributive property of multiplication

Listing down some methods to simplyfy addition.

• Doubles (such as 6 + 6)
• Near doubles: Try adding a double and the remainder. Solve 7 + 6,  (6 + 6+ 1) or (7 + 7 – 1).
• Making a ten or a multiple of 10: To add 7 + 6, I can take 3 from the 6 and put it with the 7 to make 10 and 3. This holds good even with multiples of 10 like 20, 30 40, etc
• 1 more, 1 less: Show problems such as: 8 + 1, 51 + 1, and 6 – 1, 22-1
• Place value Decomposition: 35 + 22 can be decomposed into tens and ones 30+20 added to 5+2. Or 35 – 22 can be decomposed to 30-20 plus 5-2.

Pictorial representation of the strategies above :

# Taming the tables – Tips to introduce multiplication

Some tips and tricks to start multiplication which will help you in  knowing  your times tables. I followed this approach with my daughter (she is in grade 1 rt now) and am very happy with the results. She does not have any apprehensions of which table is asked and does a quick mental maths if she does not know the answer.

Tips to approach the concept of multiplication :

I explained these concepts using lego pieces . You can use anything small and handy.

1. Now that the kids know 2 digit addition the best approach to start multiplication is by asking them to do  repeated addition. Ask them to count the objects in groups of 2 then 3 and so on.
2. Once they are thorough with repeated addition you can ask them to do skip counting.
3. Ask them to divide the total number of objects into equal groups.
4. Arrange the total number of objects in an array of row and column.

Below is a figure to illustrate how multiplication can be introduced to kids.

# Logical and analytical reasoning

#### Finding the odd one out

Step 1 : Look out for common things

Step 2 : Find a pattern in the similarities

Step 3 : Which one is different and why ? Cross out the similar ones.

Step 4 : Mark the answer .

Example :

#### What comes next

Step 1 : Look at the changes / similarities between each diagram

Step 2 : Look for a pattern in the changes

Step 3 : Do the different changes one at a time.

Step 4 : Look out for the right option

Example :