Numbers

1: un   2: bi   3: tri  4: kwar  5: kwin
6: siks 7: sep  8: ok   9: nef  10: dek

11: dek-un
12: dek-bi
13: dek-tri
14: dek-kwar
15: dek-kwin
16: dek-siks
17: dek-sep
18: dek-ok
19: dek-nef
20: bidek
21: bidek-un
22: bidek-bi
23: bidek-tri
.
.
30: tridek
31: tridek-un
.
.
40: kwardek
.
.
100:        cent
101:        cent-un
247:        bicent-kwardek-sep
1,000:      mil
1,000,000:  miliono

Notice the way numbers are written...

37:   3x10+7        tridek-sep
94:   9x10+4        nefdek-kwar
275:  2x100+7x10+5  bicent-sepdek-kwin

If numbers are MULTIPLIED they are written as one word. If ADDED they are hyphenated.

Suffix -obl-: Is used to form multiple forms of numbers.

biobla:     double
triobla:    triple
kwarobla:   quadruple

Suffix -on-: Is used to form fractions.

biono:   a half
triono:  a third
kwarono: a quarter
kwinono: a fifth

Ordinal numbers are made by adding -u

unu:       first
biu:       second
triu:      third
dek-kwaru: fourteenth

1-u:  1st
2-u:  2nd
3-u:  3rd
16-u: 16th

Simple Maths.

minus:       minus
plus:        plus
obli:        times
dividita de: divided by

Kiom esan un plus bi?
How many is one plus two?

Cu cent minus siksdek-un esan tridek-nef?
Yes, Yi esan korekta.

Kiom esan siks obli sep?
How many is six times seven?
Esan kwardek-bi.
It is forty-two.

Kiom esan dek-bi dividita de tri?
How many is twelve divided by three?
Dek-bi dividita de tri esan kwar.
Twelve divided by three is four.