modul vii

MODUL VII
Buku Siswa PERKALIAN PECAHAN
Untuk Kelas 1 SMP/MTs
By : Dr. Marsigit, M. A.
Reviewed by: Umi Baroroh

Standard of Competencies dan Basic of Competencies
Standard of Competencies
To understand and held arithmetical operation using numbers to solve problems.
Basic of Competencies
To know the fraction numbers dan held operation fraction numbers.
Indicators of Result Study
Solve multiplication operation by involve fraction.
Multiplication of Fraction.
Problem 1:
Please you do this activity as if you dividing cake with your friends.
Use a circular piece of paper to declare
the cake. Fold and cut the paper into two same parts.
How many part of the cake expressed by each piece of paper, then write the value on that piece of paper? Take one piece of it for you.
Next, cut your cake into two same parts. Then give one piece to your friend. How many part of your friend tarts tarts and your cake?
What is the proportion of your friend cake than the originally?
Problem 2:
Mother has 3 kg of wheat flour. A half of them will be given to her aunt, while one third from the remainder will be made a cake. How much the weight of the wheat flour will be made cake by mother?
To answer this problem, do the following steps:
The weight of wheat flour that will be made cake by mother is one third from a half from the complete.
The statement one third from a half can written as 1/3 x 1/2
So, the weight of the wheat flour is 1/3 x 1/2 = ....
Problem 3:
Write the mathematics sentences of one fourth from one fifth and count.
To answer this problem, do the following steps.
The statement one fourth from one fifth can write as 1/4 x 1/5
The multiplication result is 1/4 x 1/5 = ....
Problem 4:
The area of Mr. Zukri’s field is 3 1/3 ha. Mr Zukri will plant a half from the area of his field by corn. How many ha is the field of Mr Zukri’s corn?
To answer this problem, do the following steps.
The statement a half from the area of the Mr. Zukri’s field write as 1/2 x 3 1/3.
In order to we can find the multiplication result, so the mixture fraction change into ordinary fraction with constant denuminator.
The ordinary fraction of 3 1/3 is (3 x 3+1)/3 = ....
then, the multiplication form is
1/2 x 3 1/3 = 1/2 x 10/3
= 10/6
= ....
So, the area of Mr Zukri’s field is ... ha.