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can somebody explain how to do this maths question?

^^
That is correct working out.
Reply 2
Original post by neluxsan
That is correct working out.


How did they do it though, where did they get the 18 etc from..
Equate the ratios based on the colours. So you have the ratio of Red:Pink as 3:4, and Green:Red as 1:2. Therefore you can equate the red to be the same number. LCM (lowest common multiple) of 3 and 2 is 6. So multiply each ratio respectively (i.e. 3:4 would be 6:8 and 1:2 would be 3:6). You have last ratio which is White:Green as 2:9. Here you can equate the green with the green in the Green:Red ratio, which is 3:6 (since it is already equated before with Red:Pink). Here 9 is a multiple of 3, so you can multiply the Green:Red ratio by 3 to 9:18. Since you have changed the ratio for Green:Red, you need to re-equate the Red:Pink ratio, so multiply it to be 18:24, (since you want Red to be 18, so you can have 9 Green, which in turn satisfies the White:Green ratio)

Hope you understand it well!!
Reply 4
Original post by neluxsan
Equate the ratios based on the colours. So you have the ratio of Red:Pink as 3:4, and Green:Red as 1:2. Therefore you can equate the red to be the same number. LCM (lowest common multiple) of 3 and 2 is 6. So multiply each ratio respectively (i.e. 3:4 would be 6:8 and 1:2 would be 3:6). You have last ratio which is White:Green as 2:9. Here you can equate the green with the green in the Green:Red ratio, which is 3:6 (since it is already equated before with Red:Pink). Here 9 is a multiple of 3, so you can multiply the Green:Red ratio by 3 to 9:18. Since you have changed the ratio for Green:Red, you need to re-equate the Red:Pink ratio, so multiply it to be 18:24, (since you want Red to be 18, so you can have 9 Green, which in turn satisfies the White:Green ratio)

Hope you understand it well!!


Thanks, I understand.
Original post by Psaa
Thanks, I understand.


np :smile:

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