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How to know which number in the ratio is to one? (Please help)

For example, I'm currently doing an a level biology question about the ratio of final mass to initial mass of chips. The ratios change, with initially the initial mass being smaller than the final mass but this changes to the final mass being greater than the initial mass. so how do i know if its 1:x or x:1
Original post by Student2011584
For example, I'm currently doing an a level biology question about the ratio of final mass to initial mass of chips. The ratios change, with initially the initial mass being smaller than the final mass but this changes to the final mass being greater than the initial mass. so how do i know if its 1:x or x:1

if its says that its final mass to initial mass, thats the order of the ratio so final:initial
but which one do i deduce to 1? is it final 1 : initial x (ie. 0.2) or is it final x (random numbers again ie. 0.82) : 1 initial
Usually I'd keep the smaller number as the 1 but this question it changes and therefore some will be negative and some will be positive and I just dont know which is 1

Original post by mqb2766
if its says that its final mass to initial mass, thats the order of the ratio so final:initial
Original post by Student2011584
but which one do i deduce to 1? is it final 1 : initial x (ie. 0.2) or is it final x (random numbers again ie. 0.82) : 1 initial
Usually I'd keep the smaller number as the 1 but this question it changes and therefore some will be negative and some will be positive and I just dont know which is 1


Can you post the question / working youre referring to. Note in a ratio, you dont have to have one of the numbers being one.
(edited 1 year ago)
Original post by Student2011584
For example, I'm currently doing an a level biology question about the ratio of final mass to initial mass of chips. The ratios change, with initially the initial mass being smaller than the final mass but this changes to the final mass being greater than the initial mass. so how do i know if its 1:x or x:1


To determine whether the ratio should be expressed as 1:x or x:1, you need to consider the specific context and interpretation of the ratio. Let's break down the scenario you mentioned regarding the ratio of final mass to initial mass of chips.

If the initial mass is smaller than the final mass, the ratio can be expressed as x:1. In this case, "x" represents the final mass, and "1" represents the initial mass. The ratio indicates how many times the final mass is greater than the initial mass. For example, if the final mass is 10 grams and the initial mass is 2 grams, the ratio would be 10:1, indicating that the final mass is 10 times greater than the initial mass.

On the other hand, if the final mass is smaller than the initial mass, the ratio should be expressed as 1:x. In this case, "1" represents the final mass, and "x" represents the initial mass. The ratio indicates how many times the initial mass is greater than the final mass. For example, if the final mass is 2 grams and the initial mass is 10 grams, the ratio would be 1:5, indicating that the initial mass is 5 times greater than the final mass.

To determine which format (1:x or x:1) to use, carefully read the question and consider the specific information provided about the initial and final masses. The wording and context should provide clues about the appropriate interpretation of the ratio.
so for instance if the initial mass is 120g and the final mass is 90g then the ratio

Final: Initial is 90 : 120

or if you prefer

Initial : Final is 120 : 90

you can if you wish simplify the ratios to 3 : 4 and 4 : 3

then you can change so you get a 1

3 : 4 can be written as 1 : 4/3

or 3/4 : 1

& 4 : 3

can be written as 4/3 : 1

or 1 : 3/4
Original post by the bear
so for instance if the initial mass is 120g and the final mass is 90g then the ratio

Final: Initial is 90 : 120

or if you prefer

Initial : Final is 120 : 90

you can if you wish simplify the ratios to 3 : 4 and 4 : 3

then you can change so you get a 1

3 : 4 can be written as 1 : 4/3

or 3/4 : 1

& 4 : 3

can be written as 4/3 : 1

or 1 : 3/4


Yes, you've correctly analyzed the scenario and simplified the ratios. Let's go through it step by step:

Given that the initial mass is 120g and the final mass is 90g, you can express the ratio in two ways:

Final:Initial = 90:120
Simplifying this ratio gives you 3:4.

Initial:Final = 120:90
Simplifying this ratio gives you 4:3.

To express the ratio with a 1, you can either divide both terms of the ratio by the same number or write the reciprocal:

3:4 can be simplified by dividing both terms by 3, resulting in 1:4/3 or 1:1.33 (rounded to two decimal places).
Alternatively, you can divide both terms by 4, resulting in 3/4:1 or 0.75:1.

4:3 can be simplified by dividing both terms by 4, resulting in 4/3:1 or 1.33:1 (rounded to two decimal places).
Alternatively, you can divide both terms by 3, resulting in 4/3:1 or 1.33:1.

Both expressions are valid and convey the same information, but the choice between them depends on the context and the preferred way of representing the ratio.
Yes, you've correctly analyzed the scenario and simplified the ratios. Let's go through it step by step:

Given that the initial mass is 120g and the final mass is 90g, you can express the ratio in two ways:

Final:Initial = 90:120
Simplifying this ratio gives you 3:4.

Initial:Final = 120:90
Simplifying this ratio gives you 4:3.

To express the ratio with a 1, you can either divide both terms of the ratio by the same number or write the reciprocal:

3:4 can be simplified by dividing both terms by 3, resulting in 1:4/3 or 1:1.33 (rounded to two decimal places).
Alternatively, you can divide both terms by 4, resulting in 3/4:1 or 0.75:1.

4:3 can be simplified by dividing both terms by 4, resulting in 4/3:1 or 1.33:1 (rounded to two decimal places).
Alternatively, you can divide both terms by 3, resulting in 4/3:1 or 1.33:1.

Both expressions are valid and convey the same information, but the choice between them depends on the context and the preferred way of representing the ratio.
I've attached the question, it's only the table I am trying to work out but as you see there is a change in which one is greater and that's why I'm stumped.

Original post by Prof. Scarlet
Yes, you've correctly analyzed the scenario and simplified the ratios. Let's go through it step by step:

Given that the initial mass is 120g and the final mass is 90g, you can express the ratio in two ways:

Final:Initial = 90:120
Simplifying this ratio gives you 3:4.

Initial:Final = 120:90
Simplifying this ratio gives you 4:3.

To express the ratio with a 1, you can either divide both terms of the ratio by the same number or write the reciprocal:

3:4 can be simplified by dividing both terms by 3, resulting in 1:4/3 or 1:1.33 (rounded to two decimal places).
Alternatively, you can divide both terms by 4, resulting in 3/4:1 or 0.75:1.

4:3 can be simplified by dividing both terms by 4, resulting in 4/3:1 or 1.33:1 (rounded to two decimal places).
Alternatively, you can divide both terms by 3, resulting in 4/3:1 or 1.33:1.

Both expressions are valid and convey the same information, but the choice between them depends on the context and the preferred way of representing the ratio.
Original post by Student2011584
I've attached the question, it's only the table I am trying to work out but as you see there is a change in which one is greater and that's why I'm stumped.


would you please sent them as a document?
Original post by Student2011584
I've attached the question, it's only the table I am trying to work out but as you see there is a change in which one is greater and that's why I'm stumped.


Would you please sent them as a document so that I can see how to help you
Original post by Student2011584
I've attached the question, it's only the table I am trying to work out but as you see there is a change in which one is greater and that's why I'm stumped.


There is no need to send documents to anyone, especially a new user. Its best to reply directly to the thread. For part a) theyre not clear about what form they want and for the first line
3.82 : 2.79
would be "acceptable" and the column header says final : initial. You keep the order the same and dont worry about the values/whether one is greater than the other or not. Usually you express as integers though and divide out common factors
https://www.bbc.co.uk/bitesize/guides/zpxyrwx/revision/1
There are no common factors here so
382 : 279
would be the usual answer. In part c) this is coverted to a single number so 1.37 ~ 382/279
(edited 1 year ago)

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