A decimal is a number system that uses base ten to represent numbers. It uses the digits zero through nine and a decimal point to separate whole numbers from their fractional parts. Common examples include three point one four, zero point five, and twelve point seven five.
Each position in a decimal number has a specific place value. The ones place comes before the decimal point. The tenths place is the first position after the decimal point, and the hundredths place is the second position after the decimal point. In the number three point four seven, the three is in the ones place, four is in the tenths place, and seven is in the hundredths place.
Fractions can be converted to decimals by performing division. For example, one half equals zero point five because when we divide one by two, we get zero point five. Similarly, three fourths equals zero point seven five because when we divide three by four, we get zero point seven five. These visual representations show how fractions relate to their decimal equivalents.
Decimals can be used in basic mathematical operations just like whole numbers. For addition, we add two point five plus one point three to get three point eight. For subtraction, four point seven minus two point two equals two point five. For multiplication, one point two times three equals three point six. The number line helps visualize these operations by showing the positions and movements of decimal values.
To summarize what we have learned about decimals: Decimals are a base ten number system using digits zero through nine. The decimal point separates whole numbers from fractions. Each position has a specific place value like ones, tenths, and hundredths. Fractions can be converted to decimals through division, and decimals work with all basic mathematical operations.