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GRADE 7CONTENT

1.Introduction

2.Decimal Number

3.Fractions and Decimals

-Fractions to decimals

-Decimals to fractions

1.Introduction

2.Decimal Number

3.Fractions and Decimals

-Fractions to decimals

-Decimals to fractions

Introduction

Consider the following situation. Ravi has planned to celebrate pongal festival in his native place Kanthapuram. He has purchased dress materials and groceries for the celebration. The details are furnished below.

Consider the following situation. Ravi has planned to celebrate pongal festival in his native place Kanthapuram. He has purchased dress materials and groceries for the celebration. The details are furnished below.

What do you observe in the bills shown above? The prices are usually represented in decimals. But the quantities of length are represented in terms of metre and centimetre and that of weight are represented in terms of kilograms and grams. To express the quantities in terms of higher units, we use the concept of decimals.

DECIMAL NUMBER

Decimal is a term that describes the base-10 number system, probably the most commonly used number system. The decimal number system consists of ten single-digit numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. The number after 9 is 10. The number after 19 is 20 and so forth.

Decimal is a term that describes the base-10 number system, probably the most commonly used number system. The decimal number system consists of ten single-digit numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. The number after 9 is 10. The number after 19 is 20 and so forth.

Example1 Write the following in the place value grid.

(i) 0.37 (ii) 2.73 (iii) 28.271

Solution

(i) 0.37 (ii) 2.73 (iii) 28.271

Solution

FRACTIONS AND DECIMALS

CONVERTING FRACTIONS TO DECIMALS.

Step 1: Convert the fraction into an equivalent fraction with denominator 10 or 100 or 1000 if it is not so.

Step 2:Take the given fraction's numerator.Then mark the decimal point after one p,ace or two places or three places from right towards left if the given fraction's denominator is 10 or 100 or 1000 respectively.

Step 1: Convert the fraction into an equivalent fraction with denominator 10 or 100 or 1000 if it is not so.

Step 2:Take the given fraction's numerator.Then mark the decimal point after one p,ace or two places or three places from right towards left if the given fraction's denominator is 10 or 100 or 1000 respectively.

CONVERTING DECIMALS TO FRACTIONS

Step 1:Obtain the decimal

Step 2:Remove the decimal points from the given decimal and take as numerator.

Step 3:At the same time write in the denominator ,as many zero or zeros to the right of 1(one) (For example 10,100,or 1000 etc...)as there are number of digits or digits in the decimal part .And then simplify it.

Step 1:Obtain the decimal

Step 2:Remove the decimal points from the given decimal and take as numerator.

Step 3:At the same time write in the denominator ,as many zero or zeros to the right of 1(one) (For example 10,100,or 1000 etc...)as there are number of digits or digits in the decimal part .And then simplify it.