by: johanes and gopas. ratio is the comparison between 2 or more things. it can be expressed as a...
TRANSCRIPT
Maths Presentation
By: Johanes and Gopas
RATIO
Ratio is the comparison between 2 or more
things. It can be expressed as a fraction, using this (:), and using the word or.
What is Ratio?
In this topic we learn ratio. In ratio there are comparisons between objects. In here, we learn how to order, simplify, and convert.
Simplify: to simplify we need to divide two or more things (a and b) with the same amount.
Convert: In ratio sometimes we have different quantities. But in ratio we need to make the two or more in the same quantity.
Order: In ratio we need to compare two or more objects. But we need to order them based on the question. Because of that we need to be accurate at the question.
Concept
1. Liam says that he has four times as much money as
BronwynA. What is the ratio of:
i. Liam’s amount of money to Bronwyn’s amount of money
ii. ii. Bronwyn’s amount of money to Liam’s amount of money
B. Do we know the amount of money that Liam or Bronwyn actually has?
Exercise
a. i) 4 : 1 ii) 1 : 4 No, because we only know the ratio
Answer
Exercise
a. Concrete : 1 + 2 + 4 = 7 cement : 1 Fraction : =
Answer
Equivalent Ratio
Equivalent ratio is 2 different ratio with different
number that have the same amount. It is formed by multiplication and division.
What is equivalent ratio?
From the previous definitions, equivalent ratio
found when a ratio is multiplied or been divided.
To know the same amount we need to multiply or divide with the same amount.
Concept
1. N) 24 : 36 = : 3
Exercise
24 : 36 = 2 : 3 why? 36 12 So, 24 12 = 2
Answer
5) In 7M there are 16 boys and 14 girls. What
is the ratio of a) boys to girls
Exercise
Ratio: boys to girls = 16 : 14
Answer
Direct Proportion
Direct Proportion is when 1 amount increases
another amount increases at the same rate.
What is direct proportion
In this unit we also learn about direct
proportion. As it mentioned in the definition, direct proportio is when 1 amount increase and another amount increase with the same rate.
To find direct proportion you need to: you need to multiply the amount with the same rate from the information given.
Concepts
You are paid $20 per hour -How much will you get if you work 7 hours?
Example
1 hour = $20 7 hour= $140
Earnings X worked hours
Answer
Indirect Proportion
Indirect proportion is when 1 amount
decrease and the other amount increase with the same rate.
What is inderect proportion?
In inderect proportion, as mentioned in the
definition, inderect proportion is when 1 amount decrease and the other decrease with the same amount.
So you need to add and subtract with the same rate or amount.
Concepts
The further away you from the light, less
bright it is
Example
Scale
Scale is the ratio betwee the replica and the
real object.
What is scale?
To find scale, we need to divide the real object
measurements with the replica measurements.
Concept
What is the scale between the replica and the
real object if the replica is 10 m and the real object is 20m?
Example
20 So it become 1 : 2LOLOLOLOLOLOLOLOOLOLOLOLOLOLOLOLO
Answer