Page 95 - Knowledge Organiser Yr7 24-25

Knowledge Base: Mathematics TOPIC 4: Whole Numbers Year 7 | Autumn Term 2
By the end of this topic you should be able to:
• Write numbers in words and figures
• Arrange decimal numbers in order
• Multiply and divide by 10, 100, 1000
• Add and subtract positive and negative integers
• Multiply and divide positive and negative integers
• Use divisibility tests
• Recognise prime numbers
• Find the prime factor decomposition of a number
• Find the lowest common factor and highest common multiple of 2 numbers
• Recognise and use cube and square numbers, cube and square roots
Worked examples
Language
Meaning
Example
Digit
A single figure within a number
0, 1, 2, 3, 4, 5, 6, 7, 8, 9 are all digits
Place value
The value of a digit within a number
In 3.65 the 6 has a value of 6/10
Decimal point
The dot separating units from tenths
In 3.65, the decimal point separates 3 units from 6 tenths
Integer
A whole number
7 is an integer but 7.5 is not
Negative number
A number smaller than zero
-5 is a negative number
Brackets
These tell you to do this part of the calculation first
10 – 5 – 3 = 2.
But 10 – (5 – 3) = 10 – 2 = 8
Multiple
A number which is part of a numbers times table
12 and 18 are both multiples of 6
Factor
A number which exactly divides into another number
4 and 6 are both factors of 12
Product
Another word for multiplication
The product of 3 and 4 is 12
Factor Tree
A method for finding the prime factor decomposition of a number
Highest Common Factor
The biggest number which divides into both of two other numbers
6 is the highest common factor of 12 and 18
Lowest Common Multiple
The smallest number which is in the times table of two other numbers
30 is the lowest common multiple of 5 and 6
Square number Cube number
A number which is found by multiplying an integer by itself two or three times
9 = 3 x 3 = 32 (the square of 3) 27 = 3 x 3 x 3 = 33 (the cube of 3)
Square root Cube root
The opposite of a square number or cube number
= √9 Is the square root of 9
3 =∛27 is the cube root of 27
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