Presentation on theme: "The Five Important Principles"— Presentation transcript:
1 The Five Important Principles DecimalsThe Five Important Principles
2 Principle OneDecimals extend the place value system to represent parts of the whole.Write four ones and two tenths as a decimal.4.2Write six ones, four tenths and two hundredths as a decimal.6.42Why do we need a decimal before the 10ths place?Otherwise 2.0 would look like 20.
3 Principle TwoThe base ten place value system is built on symmetry around the ones place.Draw an example of a line of symmetry on your white board.ths 100thsline of symmetry
4 Principle ThreeDecimals represent parts of a whole, whole numbers and mixed numbers.Write 0.32 as a fraction.32/100Write 3.2 as a mixed number3 2/10Write 3.2 as an improper fraction.32/10Write 3.0 as an improper fraction and whole number30/10 or 3
5 Principle FourDecimals can be interpreted and read in more than one way.On your white board, find different ways to show the decimal 3.2
6 Principle Five Decimals can be renamed as other decimals or fractions. Using your white board or chart paper, shade 20 squares out of a hundred square grid.Describe as:Three fractions20/100 = 2/10=1/5Two decimals0.20 and 0.2
7 0.2 and 0.20 Are these decimals equivalent? Yes, because 20/100 and 2/10 are equivalentYes, because 0.2 equals 2 tenths and 0.20 equals 2 tenths and zero hundredths.In measurement we must be more precise though and use more decimal places. There is a lot of difference between 3.20 metres and 3.2 metres when you are building a bridge! The more decimal places, the more precise the measurement.
8 Equivalent Fractions and Decimals Find the decimal equivalent:0.5 or 0.500.251/80.125How did we do this?Find the decimal equivalent of 1/3 by dividing the denominator into the numerator.This is a repeating decimal.Why does it repeat?We show this by placing a line over it.