Unit 7.1

#

Decimals, Hundreds, Thousands

Numbers

The **decimal** numeral system has ten as its base. A decimal number, or just a decimal, refers to any number written in decimal notation.

One **hundred** or 100 is the natural number following 99 and preceding 101.

One **thousand** or 1000 is the natural number following 999 and preceding 1001. In most English-speaking countries, it is often written with a comma separating the thousands unit: 1,000.

Decimals: 0.10 = 1/10, 10/100; 0.01 = 1/100; 0.001 = 1/1000; etc.

Hundreds: 100 = one hundred; 200 = two hundred; 500 = five hundred; etc.

Thousands: 1000 = one thousand; 10,000 = ten thousand; 100,000 = one hundred thousand; etc.

Millions: 1,000,000 = one million; 10,000,000 = ten million; 100,000,000 = one hundred million; etc.

- 125 = a/one hundred and twenty five;
- 5 459 095 = five million four hundred and fifty nine thousand and ninety five.

- We can use either “a” or “one” at the beginning of a number (from 100 and on);
- When we say numbers we don’t use the plural.

In formal writing it is better to write the number in letters.