MODULE IV Student Book PERCENT AND permil For Class 1 SMP / MTs

MODULE IV

Student Book

PERCENT AND permil

For Class 1 SMP / MTs

By : Marsigit

Reviewed by : Eka Sulistyawati

A.    Basic Competencies and Standards Competency

Standards of competence :

Understanding and perform arithmetic operations number in problem solving

Basic Competence:

Know fractions and perform operations of fractions

B.     Learning Outcome Indicators

• Obtain percent

• Obtain permil

C.     Percent and the permil

Issue 1:

Make Percent model by counting the number of shaded areas. Make a plot with a width of 10 unit area and length of 10 unit area, for example as follows:
Try you count, of the 100 small plots how many small plots are shaded?
Did you get 21 pieces? If it, then it can be said that: the number of small plots shaded is 21 out of 100 that exist, or say as much as 21%. Do you conclude that: 21% point is 21/100 In succession:

35% point is .........

67% point is ...........

50% point is ...........

100% point is ..........

Issue 2:

In everyday life you are sometimes asked to write percent shape of a quantity is known.

36% point is 36/100 = 9/25, So 36% = .......

50% point is 50/100 =1/2, so 50% = .......

100% means that the 100/100 = 1 so 100% = .......

Issues 3: If the 2/3 part of earth covered by water. Expressing it in the form percent?
Take these steps: Earth is covered with water 2/3 parts of the earth.
Then written 2/3 x 100% of the earth. Or written 2x100 / 3 %

Obtained 200/3 %. Then use a calculator to divide 200 by 3. So the earth is covered with water is 66.666666%.

Issues 4: Declare ¼ as a percent. Take these steps:

We find fractions equivalent to ¼ whose denominators 100

¼ = ..../100

¼ = 1x25/4x25 =25/100

¼ equivalent to 25/100 % = 25%. So ¼  can be written as a 25%

Issue 4:

Permil fractions used to express salinity (salt content) sea ​​water. For example, the Red Sea salinity is 41 ‰. That is, there are 41 grams salt in each 1000 grams of water in the Red Sea. If the percent said percent fractional then the fractional states permil thousandths. Permil denoted by ‰. For example, 10 permil denoted by 10 ‰. Permil can be expressed in the form common fractions as follows.

10 ‰ = 10/1000 =..............

Issues 5: Change the form of fractional ¼  in the form of permil

Did you find:

¼ = ¼  × 1000 ‰  = 250 ‰

Issues 6: Change the form of 750 ‰ in the form of common fractions. Do you find such a following?

750 ‰ =750/1000 = 750:250 / 1000:250= ¾ 

D.    Your conclusions?

Common fraction or mixed fraction can be expressed in the form decimal fractions. In other hand, can be expressed in decimal fractions common fractions or mixed fractions. Percent have a meaning of "percent". You can write a comparison 25/100 as 25%, 65/100 as 65%,10/100 as 10%, 40/100 as a 40% and so on.