### Chap 9: Rate, Ratio and Proportion

Self Directed Learning (week 9)
2 tasks attached to be completed

• What is/ the key difference/s between ratio and proportion?
• What are the rules you have to observe in ratio and proportion?
Go through the following activities
[the critical activities are identified with *]
factsheet include the following:
1. What is ratio? 2. Understanding direct proportion? 3. Using Direct Proportion
4. Simplifying ratios? 5. Tips for ratio and proportion sums 6. Key words

simple game to practice ratio:

worksheet 2, 3 & 5 compulsory (*)

Self directed quiz with 3 different level of difficulties (*)

Task 2 : [to be submitted]
before completing the assignment review what you have covered in this chapter

1-02 & 1-05 : use your exercise books
1-08 & 1-09 : use fool scap papers
[akan datang]

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2. A ratio is a comparison of two numbers. We generally separate the two numbers in the ratio with a colon (:). Suppose we want to write the ratio of 8 and 12.
We can write this as 8:12, and we say the ratio is eight to twelve.
A proportion is an equation with a ratio on each side. It is a statement that two ratios are equal. If the proportion is cross-multiplied the products are equal.
3:4 = 6:8 is an example of a proportion.

3. ratio for example: 4:8, can be simplified, to 1:4, but a proportion cannot, and a proportion is that a ratio is equal to another ratio.

4. A ratio is a comparison of two numbers. Suppose we want to write the ratio of 8 and 12.
We can write this as 8:12 or as a fraction 8/12, and we say the ratio is eight to twelve.

Example:

Jeannine has a bag with 3 videocassettes, 4 marbles, 7 books, and 1 orange.
Find the ratio of the following~3:4:7

Proportion:

A proportion is an equation with a ratio on each side. It is a statement that two ratios are equal.
3/4 = 6/8 is an example of a proportion.

When one of the four numbers in a proportion is unknown, cross products may be used to find the unknown number. This is called solving the proportion.

Example:

Solve for n: 1/2 = n/4.
Using cross products we see that 2 × n = 1 × 4 =4, so 2 × n = 4. Dividing both sides by 2, n = 4 ÷ 2 so that n = 2.

5. A ratio is a comparison of numbers that can be expressed as a fraction.
e.g1 = 2 to 3
= 2:3
= 2/3

A proportion is a statement that one ratio is equals to another ratio.
e.g1.1 = 4:8
= 1:2

e.g1.2 = 3:6
= 1:2

6. Abilash

A ratio is a dimensionless, or unitless, quantity denoting an amount or magnitude of one quantity relative to another.A ratio is also a comparison of numbers that can be expressed as a fraction .

Proportion is a correspondence among the measures of the members of an entire work, and of the whole to a certain part selected as standard.A proportion is a statement that one ratio is equal to another ratio .

-Some has been taken from dictionary . -

7. What is/ the key difference/s between ratio and proportion?
A ratio is a comparison of numbers that can be expressed as a fraction.
A proportion is a statement that one ratio is equal to another ratio.
What are the rules you have to observe in ratio and proportion?
Ratio:The order of the number is critical
Proportion: In a proportion, you will notice if you cross-multiply the terms of a proportion, those cross products are equal.The fundamental principal of proportion enables you to solve problems in which 1 number of the proportion is not known.

8. A ratio is a comparison of numbers that can be expressed as a fraction, while a proportion is that one ratio is equal to the other one. If we cross multiply a proportion, the cross products are equal.

9. Ratio is a comparison of two numbers by division. A proportion is a statement where two ratios are equal.

10. Ratio:

-The first operation to perform on a ratio is to reduce it to the lowest terms.
-The order of the numbers is critical

Proportion:

-Ratios form a proportion when they are equal to each other.
-The fundamental principle of proportions enables you to solve problems in which one number of the proportion is not known.
Eg, if it's n/3 = 8/12, we can find out the value of n

11. For Ratio,the order of the numbers is critical

For proportion,cross multiply the terms of a proportion,cross products are equal. Proportion enables us to solve problems which one proportion is not known.Careful to place the same question corresponding positions in the proportions

12. A ratio is (a no.) : (a no.) eg. 1:2
the ratio must be in the lowest term.

A proportion is a combination of two equal ratios (eg. 1:2 = 2:3)
The meaning of both ratio must same.

13. Ratio is a comparison of two or more number which should be in the simplest form. E.g. 5 : 7 , 4 : 9 : 11.
A proportion is two equal ratio which is not in the simplest form. We could cross multiply a proportion to get the simplest product and it should be equal.

14. A ratio is a comparisons of numbers and also another way to represent fractions.
For example, 7:8 can also be expressed as 7/8.
A proportion is a statement that one ratio is equals to another ratio.
For example, 3:6=6:12.

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16. Ratios
A ratio shows the relative sizes of two or more values.

Ratios can be shown in different ways:
3 : 1 Using the ":" to separate example values
¾ as a fraction, by dividing one value by the total (3 out of 4 boxes are blue)
0.75 as a decimal
75% as a percentage

Example: if there is 1 boy and 3 girls you could write the ratio as:
1:3 (for every one boy there are 3 girls)
1/4 are boys and 3/4 are girls
0.25 are boys (by dividing 1 by 4)
25% are boys (0.25 as a percentage)

Proportion

A proportion is an equation with a ratio on each side. It is a statement that two ratios are equal.
3/4 = 6/8 is an example of a proportion.

Example:

Solve for n: 1/2 = n/4.
Using cross products we see that 2 × n = 1 × 4 =4, so 2 × n = 4. Dividing both sides by 2, n = 4 ÷ 2 so that n = 2.

17. The rules I observe in ratio and proportion:

Ratio-A ratio can exist only between units of the same kind,(e.g. Percent to percent, grams to grams, dollars to dollars) In other words, the units must be constant.

Proportion-It is a maths statement where two ratios are equal and to do that we must cross product.

18. ratio:The order of numbers is crucial

proportion:one ration will be equal to another
cross products would be equal
The fundamental principle of proportions enable to solve problems in which one number of the proportion is not known.

19. A ratio is like a fraction, it compares the 2 numbers. We usually use a colon to write ratios (A:B). We can also write it as a fraction or write it as A to B.

Example:
The number of iFlush sold in 2009 was 13678 sets. The number of iFlash sold was 54712. Find the ratio of the number of iFlush sold to the number of iFlash sold.
13678:54712 = 1:4

A proportion is a statement which says that one ratio is equal to another ratio.

E.g. 14578:43734 = 2:6

-Christopher Nah

20. Rules observed in Ratio and Proportion

Ratio

1. The ratio must always be written in order.
eg: There are 5 cats, 4 dogs and 2 rats. Write the ratio of number of dogs to cats to rats?

2.Most ratios must be simplified
eg: 12/4
Ans: 3/1 in other words 3

Proportion

1.To find the missing number in the fraction always use cross multiplication.
eg:n/27 = 1/9
= 9 x n = 27 x 1
= 9 x n = 27
=27 ÷ 9
=3

2. Proportion is always about the missing number.
eg: n/27 =1/9
This shows that n represents the missing number.