Direct ProportionDirect ProportionDirect ProportionDirect Proportion

November 6, 2008November 6, 2008

Let us try to reflect on what we

have done yesterday.

What is the connection of making pastillas with Math specifically in ratio and proportion?

Let us try to reflect on what we

have done yesterday.

Were you able to tolerate some people in your group and how did you do it?

Let us try to reflect on what we

have done yesterday.

How can we accept people who have different choices, opinions, and tastes from us?

Let us try to reflect on what we

have done yesterday.

Was there a time that your patience was tested by another member? How did you deal with it? How can we accept other people’s differences?

What is a direct

proportion?Two quantities are directly proportional if an increase in one quantity corresponds to a constant increase in the other quantity, or if a decrease in one quantity corresponds to a constant decrease in the other quantity.

The more you eat,the more you grow.

The lesser the number of items,

the smaller the amount to pay.

What are other examples of direct proportion?

The more sugar you add in the pastillas,

the sweeter it will be.

What are other examples of direct proportion?

The faster the speed,the greater the distance.

What are other examples of direct proportion?

The more the number of persons,

the more food is required.

What are other examples of direct proportion?

The less sleep you had,the less energy

you have.

Let us try looking at one word problem.

Maita earns 450 pesos in selling sampaguita garlands on 4 Sundays. How many Sundays will it take her to earn 1,350 pesos?

Is this a problem involving direct proportion? Why do you say so?

Yes it is, because the more Sundays Maita sells sampaguita, the more earnings she will have.

Maita earns 450 pesos in selling sampaguita garlands on 4 Sundays. How many Sundays will it take her to earn 1,350 pesos?

To solve this problem, after knowing what is asked, it’s better to list the given facts or numbers using a table.

No. of Sundays

Earnings

4 450

n 1,350

Let n represent the number asked for in the problem

Maita earns 450 pesos in selling sampaguita garlands on 4 Sundays. How many Sundays will it take her to earn 1,350 pesos? No. of

SundaysEarnings

4 450n 1,350

Form two ratios given the numbers in the table. Equate the first ratio to the second ratio.

1350

4504

n

Maita earns 450 pesos in selling sampaguita garlands on 4 Sundays. How many Sundays will it take her to earn 1,350 pesos?

No. of Sundays

Earnings

4 450n 1,350

Solve for the value of n by using cross-multiplication. Indicate the proper label.

1350

4504

n

450

13504n

450

5400n

Sundaysn 12

Maita earns 450 pesos in selling sampaguita garlands on 4 Sundays. How many Sundays will it take her to earn 1,350 pesos?

No. of Sundays

Earnings

4 45012 1,350

Therefore, Maita should sell sampaguita garlands on 12 Sundays to earn 1,350 pesos.

Let’s practice!!!

By pair, answer Challenge Yourself #s 1-5 on pages 205-206.

Since this is a pair work, seat beside your partner and work quietly. Help each other answer the word problems. If there are questions, approach the teacher.

Practice more!

Answer Challenge Yourself #s 6-7 on page 206 of your work text.

Bring coloring materials tomorrow. Be sure you have the colors red, yellow, and blue.

HOMEWORK

Quiz # 5

Comparing Quantities using RatioSimplifying RatiosSolving for the Unknown in a

ProportionDirect Proportion Indirect/Inverse ProportionPartitive ProportionWord Problems

November 14, 2008 (Friday)

TOPICS: