Page 244 - NUMINO TG_2A
P. 244
15Counting in Groups Unit
CMath Vo abulary Multiplication: repeated addition of the same number
Who Invented the Multiplication Sign, ^? Explain the origin of the multiplication sign,
which expresses repeated addition in a
When you add the same simpler manner.
numbers, it is a good idea Have students discuss the different
to use ^. mathematical signs they know. Have them
discuss what they mean as well.
“A number plus 2 is 5.” A1: There are “ ” and “ .” “ ” means add,
We can write this as “ + 2 = 5.”
In math, signs are very important. and “ ” means subtract.
We can use them to write simple number A2: There is “ .” It means “equal to.”
sentences. A3: We can also say that numbers such as 1,
Oughtred 2, and 3 are also signs.
The multiplication sign, ^, was introduced 100 years after + and -.
In 1631, William Oughtred first used ^ in his book,
The Key to Mathematics. Oughtred used more than 150 math signs
in his book. Some of them, like ^, are still used today.
Tell the students to think about the mathematical signs they know.
How could they write the multiplication sign “ ” to make it read differently
from the letter “x”?
15. Counting in Groups 141
2A Unit 15 227
CMath Vo abulary Multiplication: repeated addition of the same number
Who Invented the Multiplication Sign, ^? Explain the origin of the multiplication sign,
which expresses repeated addition in a
When you add the same simpler manner.
numbers, it is a good idea Have students discuss the different
to use ^. mathematical signs they know. Have them
discuss what they mean as well.
“A number plus 2 is 5.” A1: There are “ ” and “ .” “ ” means add,
We can write this as “ + 2 = 5.”
In math, signs are very important. and “ ” means subtract.
We can use them to write simple number A2: There is “ .” It means “equal to.”
sentences. A3: We can also say that numbers such as 1,
Oughtred 2, and 3 are also signs.
The multiplication sign, ^, was introduced 100 years after + and -.
In 1631, William Oughtred first used ^ in his book,
The Key to Mathematics. Oughtred used more than 150 math signs
in his book. Some of them, like ^, are still used today.
Tell the students to think about the mathematical signs they know.
How could they write the multiplication sign “ ” to make it read differently
from the letter “x”?
15. Counting in Groups 141
2A Unit 15 227
