Std. :- 5th Sub. :- Mathematics Chapter no. 14 Decimal Fractions :Introduction

Decimal Fractions :Introduction 2.Reading 3.Place value 4.Conversion

Decimal Fraction : meaning Observe the following fractions 13 17 17 10 7 3 100 5 A fraction which has 10, or 100, or 1000, or 10,000 or such multiples of 10 in the denominator is called a decimal fraction.

How do I know what kind of decimal it is? The name of a decimal is determined by the number of places to the right of the decimal point Number of Places Decimal Name Example 1 tenths 0.7 2 hundredths 0.05 3 thousandths 0.016

What are mixed decimals? Mixed decimals are numbers with both whole numbers and decimals The name of a whole number is determined by the number of places to the left of the decimal point In the number 128.765, 1 is in the hundreds place, 2 is in the tens place, 8 is in the ones place, 7 is in the tenths place, 6 is in the hundredths place, and 5 is in the thousandths place

How do you read decimals? To read a decimal correctly, first find the decimal point Whole numbers are to the left of the decimal point; any numbers to the right of a decimal point form a decimal fraction Say “and” for the decimal point The decimal 2164.511 is read as “two thousand, one hundred sixty-four and five hundred eleven thousandths”

Zeros after the decimal point Writing extra zeros after the decimal point does not change the value! The decimals 0.2, 0.20, and 0.200 are equivalent decimals

Practice HERE ARE SOME PRACTICE PROBLEMS IN WHICH I WILL WORK THROUGH WITH YOU TO MAKE SURE THAT YOU UNDERSTAND THE MAIN CONCEPTS COVERED.

Exercise 1 Write the decimals. Five thousandths Ninety-four thousandths Three hundred thirty-six and sixty-nine hundredths

Exercise 2 Write each decimal in words. 7884.011 5592.4 4.203 612.250 10.44

Fractions to Decimals Express as a decimal. Here it is best to divide out:

Express as a decimal. Here it is easier to make the denominator a multiple of 10

Converting decimals to fractions: Convert fractions to decimals by dividing numerator by denominator: Multiplying a decimal by a multiple of 10: 3.27x10 = 32.7, 3.27x100 = 327, 3.27x1000 = 3270 Dividing a decimal by a multiple of 10: 43.1÷10 = 4.31, 43.1÷100 = 0.431, 43.1÷1000 = 0.0431 Decimals are fractions like tenths, hundredths, thousandths etc. which have denominators of 10 and multiples of 10 such as 100, 1000 etc. So we can convert a decimal into a fraction by taking the number before the decimal point as the whole number and the numbers after the decimal point as a fraction with the denominator as 10 for one decimal place, 100 for two decimal places, 1000 for three decimal places etc. E.g. We can convert a fraction to a decimal by dividing the numerator by the denominator. E.g. 1/8 = 1÷8 = 0.125. To multiply a decimal by 10 we move the decimal point one place to the right. To multiply by 100 we move the point two places to the right etc. E.g. 3.27x10 = 32.7, 3.27x100 = 327, 3.27x1000 = 3270 To divide a decimal by 10 we move the decimal point one place to the left. To divide by 100 we move the point two places to the left etc. E.g. 43.1÷10 = 4.31, 43.1÷100 = 0.431, 43.1÷1000 = 0.0431 BREAK FOR EXERCISES 12.50 – 1.05pm zero after decimal point is to keep place value 13

Express as a decimal in its simplest form

Exercise 3 In what place (on the place value chart) is the underlined digit? Write the answer. 1.475 3.763 7780.215 412.407 902.103

Reference :- Text Book Web