MODUL III Buku Siswa PECAHAN DESIMAL Untuk Kelas 1 SMP / MTs

MODUL III

Buku Siswa

PECAHAN DESIMAL

Untuk Kelas 1 SMP / MTs

By : Marsigit

Reviewed by : Eka Sulistyawati

A.    Basic Competencies and Standards Competency

Standards Competence :

Understanding and perform arithmetic operations numbers in problem solving
Basic Competence :

Know fractions and perform operations of fractions

B.     Learning Outcome Indicators

Getting a decimal fraction

C.    Decimal fractions

Issue 1:

Advertising in a newspaper mentions "For Sale HP in good condition guarantee and the price of 0.7 million ". What is the meaning of 0.7 ?

Issue 2:

0.35 crown rose flowers have fallen. Express 0.35 in form of simple fractions!
0, 35 = 35/100 = 7/20 (numerator and denominator is divided by 5). Explain why 0.35 = 7/20

Issue 3:

Write 0.775 as a fraction in the simple fractions form. Take these steps: 0.775 decimal fractions can be written 775/1000. Then the fraction can be simplified by: numerator and denominator are divided by the same number. Do you find that the best divisor is 25? Because 775 divided by 25 the results is 31/1000 divided by 25 the results 40. Is the decimal fraction 0.775 can be written with simple fractions 31/40.

Do you conclude that if the value of a decimal more than 1 then the decimal number can be written as a mixed fractions. Instead we can write a fraction in the form
decimal fractions in the usual form.

Issues 4:

Write the 3/9 into a decimal fraction?Take these steps: We can write decimal fractions by dividing the numerator by denominator as shown as follows:
(using “Poro Gapit” ).

Then 3/9 can be written as .....Or if you have difficulty in making the division you
can use a calculator.

Issue 5:

Investigate where you can get recurring decimals or no recurring decimal.

D.    Your conclusions?

Common fraction or mixed fraction can be expressed in the form decimal fractions. In other hand, can be expressed in common fractions or mixed fractions. Do you find that the resulting decimal contains some number 3 or number 3 are repeated. It is said that decimal fraction 0.3333 .. as a recurring decimal. But 0.35 decimal say no recurring decimals.