Page 243 - NUMINO TG_2A
P. 243
Math Story A Lazy Mathematician and Multiplication
jOb ective Know the basis of multiplication.
1. Textbook Instructions Math Story A Lazy Mathematician and Multiplication
Explain how repeated addition is related to Did you learn how to skip-count? Let’s count the stars in
multiplication sentences. the sky!
The following is an example of a class
explaining the relationship between repeated 3+3 +3 +3+3 +
addition and multiplication sentences.
Say, we are counting the stars in the sky. Counting the stars like that will take you forever! No!
How would you count them? Count them You might want to try, but if you were me, you would use
one by one. multiplication instead.
We can count them one by one, but it Count the stars like this:
would be easier to use what we have
learned before and count them using equal 3+3+3+3+3+3+3+3+3=9^3
groups. Let’s count in groups of 3.
How can we count? 3 3 3 3 3 3... 5+5+5= 3 ^5
That’s correct. But what kind of
problems can we have if we continue to do 2+2+2+2= 2 ^ 4
this?
A1: There won’t be any room left to write. 3+3+3+3+3= 3 ^ 5
A2: It is tiring.
A3: It will feel more tedious as we write and 4+4+4= 4 ^ 3
write. Apply this method to the previous page for more
Yes. That is exactly what the mathematicians practice on making multiplication sentences from
thought. So they found a way to write repeated addition.
addition sentences with more than 2
numbers that are the same with a single 140
sign.
It is “ ” (multiplication sign).
Let’s use “ ” to solve the following
problems.
2. Build Understanding
Multiplication sentences
The concept of multiplication is “adding the same numbers more than two times” and starts from counting
in groups.
So, from multiplication sentences, we can figure out how many groups there are and how many are in each
group.
Example: 5 3 5 groups of 3.
226 NUMINO Teacher s Guide
jOb ective Know the basis of multiplication.
1. Textbook Instructions Math Story A Lazy Mathematician and Multiplication
Explain how repeated addition is related to Did you learn how to skip-count? Let’s count the stars in
multiplication sentences. the sky!
The following is an example of a class
explaining the relationship between repeated 3+3 +3 +3+3 +
addition and multiplication sentences.
Say, we are counting the stars in the sky. Counting the stars like that will take you forever! No!
How would you count them? Count them You might want to try, but if you were me, you would use
one by one. multiplication instead.
We can count them one by one, but it Count the stars like this:
would be easier to use what we have
learned before and count them using equal 3+3+3+3+3+3+3+3+3=9^3
groups. Let’s count in groups of 3.
How can we count? 3 3 3 3 3 3... 5+5+5= 3 ^5
That’s correct. But what kind of
problems can we have if we continue to do 2+2+2+2= 2 ^ 4
this?
A1: There won’t be any room left to write. 3+3+3+3+3= 3 ^ 5
A2: It is tiring.
A3: It will feel more tedious as we write and 4+4+4= 4 ^ 3
write. Apply this method to the previous page for more
Yes. That is exactly what the mathematicians practice on making multiplication sentences from
thought. So they found a way to write repeated addition.
addition sentences with more than 2
numbers that are the same with a single 140
sign.
It is “ ” (multiplication sign).
Let’s use “ ” to solve the following
problems.
2. Build Understanding
Multiplication sentences
The concept of multiplication is “adding the same numbers more than two times” and starts from counting
in groups.
So, from multiplication sentences, we can figure out how many groups there are and how many are in each
group.
Example: 5 3 5 groups of 3.
226 NUMINO Teacher s Guide
