### Numbers

-187 : minus one hundred and eighty seven

33,333 : thirty-three thousand, three hundred and thirty-three

1,000,000 : one million

2,000,000,000 : two billion

9,000,000,000,000 : nine trillion

Notes:

- always use a comma with numbers greater than 999.
- don’t say ‘3 millions’ – although you might hear people say things like ‘It cost millions and millions of dollars’.
- if you have an old dictionary you might read that there are two options for billion – that is no longer true.

54.25 : fifty-four point two five

1^{10} : one to the power of ten

-5.5 x 10^{10} : minus five point five times ten to the power of ten

8 x 10^{-3} : eight times ten to the minus three

### Fractions

1 ½ : one and a half

2 ⅓ : two and a third

-3 ¼ : minus three and a quarter

4 ⅕ : four and a fifth

⅜ : three-eighths

0.002 : two thousandths

### Equations and Operations

3n + 4x : three n plus four x

1 – 2n : one minus two n

3+3=6 : three plus three equals six

18-8=10 : eighteen minus eight equals ten

3/5=0.6 : three divided by five equals zero point six

5! = five factorial

Notes:

- For 0.6 you can also say nought point six

### Greater and Less Than

x>y : x is greater than y

x≥y : x is greater than or equal to y

x<y : x is less than y

x≤y : x is less than or equal to y

Notes:

You can also say ‘x is smaller than y’

### Exponentials and Roots

2^{2} : two squared

4^{3} : four cubed

6^{4} : six to the power of four

8^{10} : eight to the power of ten

10^{-1} : ten to the minus one

√3 : the square root of three

3√32 : the cube root of thirty two

5√64 : the fifth root of sixty four

### Miscellaneous Maths Vocabulary

odd number : 1,3,5,7, etc

even number : 2,4,6, etc

denominator : the number below the line

numerator : the number above the line

left bracket : [

right bracket : ]

curly bracket (AKA braces) : { }

exponent : how many times to use that number in a multiplication

factorial : the product of a number and all the numbers below it. (4! = 4 x 3 x 2 x 1)

infinity : ∞ : a number greater than all the atoms of ice cream I’ve ever eaten

product : the answer when numbers are multiplied

ratio : the relationship between two numbers

integer : a whole number

rational number : a number that can be made by dividing two integers

irrational number : a real number that cannot be made by dividing two integers

prime : a number that is divisible only by itself and 1

coefficient : a number used to multiply a variable