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HSC Stuff => HSC Maths Stuff => HSC Subjects + Help => HSC Standard Mathematics => Topic started by: Droolv on February 12, 2017, 12:40:17 pm

Title: Ratios help!
Post by: Droolv on February 12, 2017, 12:40:17 pm

Hey guys, just needed some help with this question, I can't wrap my head around it  :-\ Thanks in advance

In a candy shop, the ratio of Red jellybeans to Blue jellybeans is 3:7, whilst the ratio of Blue jellybeans to Green jellybeans is 8:11. Find the ratio of Green jellybeans to Red jellybeans.

Title: Re: Ratios help!
Post by: natdogg on February 12, 2017, 01:15:46 pm

It'll help to find a common ratio, by that I mean:

The lowest common multiple of 7 and 8 (the blue jellybean ratios) is 56, and you know that 3:7 is the same as 24:56, and 8:11 is the same as 56:77.
So now you have the ratio of red to blue to green of 24:56:77

Therefore ratio of Green to red jellybeans is 77:24

Title: Re: Ratios help!
Post by: Droolv on February 12, 2017, 02:12:11 pm

Thanks so much!