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Integer meaning

Another name for a whole number- either a positive or negative number, or zero


What are 3 different forms of Rational numbers

1. Integers
2. Fractions
3. Terminating or recurring decimals


What are Irrational numbers

Numbers that can't be written as fractions— they're never-ending, non-repeating decimal. Square roots of +ve integers are either integers or irrational. Surds are numbers or expressions containing irrational roots


What does BODMAS stand for and what is it used for


Tells you the order in which these operations should be done


What are multiples of a number

A numbers times table


What are factors of a number

All the numbers that divide into the number


What is a prime number

A number which doesn't divide by anything, apart from itself and 1— i.e. It's only factors are itself and 1. ( the only exception is 1, which is NOT a prime number)


How to find prime factors of a number

Use a factor tree:
1. Start with the number at the top, and split it into factors
2. Every time you get a prime, ring it
3. Keep going until you can't go further then write the primes out in order. If there's more than one of the same factor, write them as powers


What is the LCM

'Least common multiple' is the smallest number bet that will divide by all the numbers in the question.


What is the HCF

'Highest common factor' is the biggest number that will divide into all the numbers in the question


How do you simplify a fraction

Divide numerator and denominator by same number, till they won't go further


How to multiply fractions

Simplify then multiply too and bottom numbers separately


How to divide fractions

Flip the second and multiply


How to add and subtract fractions

Make sure denominators at the same then add/subtract numerators only


How to find common denominator

Find a number that all denominators divide into- this is common denominator


How to fraction -> decimal

Divide numerator by denominator


How to decimal -> percentage



How to percentage -> decimal

Divide by 100


How to terminating decimal -> fraction

The digits after the d.p go on top and a power of 10 on the bottom- with the same number of zeros as there were decimal places


How to recurring decimal -> fraction

1. Name decimal x
2. Multiply x by a power of 10 to move it past the decimal point by one full repeated lump
3 subtract x by the power of 10 x to get rid of decimal part
4. Then divide to leave x and simplify if possible


How to fractions into recurring decimals

Find an equivalent fraction with all mined on denominator. The numerator will tell you the recurring part


How to round to a given number of decimal places

- identify position of 'last digit' from the number of decimal places.
- then look at digit to the right (the decider)
-if decider 5 or above round up last digit, if decider 4 or less leave digit as is


Rounding to significant figures

The first s.f of any number is the first digit which isn't zero. The 2nd,3rd,4th,etc. s.f follow on immediately after the 1st, regardless of being zeros or not zeros


How to estimate calculations

Round all numbers to 1 sig fig


How to estimate square roots

Find 2 square numbers, one either side of the number you're given. Decide which number it's closest to, and mar a sensible estimate of the digit after the decimal point


What are upper and lower bounds

When a measurement is rounded to a given unit, the actual measurement can be anything up to half a unit bigger smaller


What are the three rules of standard form

A x 10^n

1. Front number (A) must always be between 1 and 10
2. The power of 10 (n) is how far the decimal point moves
3. n is positive for big numbers and negative for small numbers


Multiplying and dividing standard form

1. Rearrange to put front number and powers of 10 together
2. Multiply/divide front numbers, and use the power rules to multiply/divide the powers of 10
3. Make sure answer is in standard form


Adding and subtracting standard form

1. Make sure powers of 10 are same
2. Add/subtract front numbers
3. Convert answer to standard form if necessary