Adding and Subtracting Decimals

Unit 3 Lesson 4

10 millimeters = 1 centimeter

10 centimeters = 1 decimeter

A decade is 10 years. A decagon has 10 sides.

The decathlon is a combined event of ten track

and field events.

A decimal is a symbol that

defines place value by 10.

Deci-

centipede means “hundred feet”, but no centipede has that many feet.

The 1800s (1800-1900) are called the 19th Century.

100 years

The 1900s (1900-2000) are called the 20th Century.

The 2000s (2000-2100) are called the 21st Century.

100 years

She is 100 years old and is a called

a centenarian.

Centi-

Millipede means “thousand footed, but no millipede has that many

feet

1011

2011 A millennium is a period

of 1,000 years. April 1011 to April 2011 is

a millennium.

Milli-