Cardinal Numbers
0 – zero
1 – one
2 – two
3 – three
4 – four
5 – five
6 – six
7 – seven
8 – eight
9 – nine
10 – ten
11 – eleven
12 – twelve
13 – thirteen
14 – fourteen
15 – fifteen
16 – sixteen
17 – seventeen
18 – eighteen
19 – nineteen
20 – twenty
21 – twenty-one
22 – twenty-two
23 – twenty-three
24 – twenty-four
25 – twenty-five
30 – thirty
31 – thirty-one
32 – thirty-two
33 – thirty-three
34 – thirty-four
35 – thirty-five
40 – forty
50 – fifty
60 – sixty
70 – seventy
80 – eighty
90 – ninety
100 – a hundred, or one hundred
101 – a hundred and one
102 – a hundred and two
110 – a hundred and ten
111 – a hundred and eleven
200 – two hundred
300 – three hundred
1,000 – a thousand, or one thousand
2,000 – two thousand
1,000,000 – a million, or one million
1,000,000,000 – a billion, or one billion
1,000,000,000,000 – a trillion, or one trillion
Ordinal Numbers
1st – first
2nd – second
3rd – third
4th – forth
5th – fifth
6th – sixth
7th – seventh
8th – eighth
9th – ninth
10th – tenth
11th – eleventh
12th – twelfth
13th – thirteenth
14th – fourteenth
20th – twentieth
21st – twenty-first
22nd – twenty-second
23rd – twenty-third
24th – twenty-forth
25– twenty-fifth
30th – thirtieth
31 – thirty-first
32 – thirty-second
33rd – thirty-third
34th – thirty-forth
35th – thirty-fifth
40th – fortieth
50th – fiftieth
60th – sixtieth
70th – seventieth
80th – eightieth
90th – ninetieth
100th – a hundredth, or one hundredth
1,000th – a thousandth, or one thousandth
1,000,000th – a millionth, or one millionth
1,000,000,000th – a billionth, or one billionth
1,000,000,000,000th – a trillionth, or one trillionth
Fractional Numbers
1/2 – half
1/3 – a third, or one third
3/4 – three quarters
5/8– five-eights
1 1/4 – one and a quarter, or one and one quarter
2 2/3 – two and two thirds
3 15/16 – three and fifteen-sixteens
1/10 – a tenth, or one tenth
1/20 – one twentieth
1/100 – one hundredth
Equations
3 > 1 – three greater than one
1 < 3 – one less than three
1 + 5 = 6 – one plus five equals six
5 – 1 = 4 – five minus one equals four
1 – 5 = -4 – one minus five equals minus four
10 x 10 = 100 – ten times ten equals a hundred
100 % 10 = a hundred divided by ten equals ten
2<sup>2</sup> = 4 – two squared equals four
3<sup>3</sup> = 3 – three cubed equals twenty-seven
√4 = 2 – the square root of four is two
<sup>3</sup>√27 = 3 – the cube root of twenty-seven is three
10 <sup>4</sup> = 10,000 – ten to the fourth power equals ten thousand
Irrational Numbers
π – pi
e – ee
