ratio and percentages in algebra help URGENT

m:n = 3:8 and r is 20% of n. Work out m:r.
How would you work this out? please help.

(edited 3 years ago)

r=0.2n

\dfrac{m}{r}=\dfrac{m}{0.2n} = \dfrac{5m}{n} =\dfrac{15}{8}

(edited 3 years ago)

r=0.2n

\dfrac{m}{r}=\dfrac{m}{0.2n} = \dfrac{5m}{n} =\dfrac{15}{8}

thank you for your reply! :smile:

but i don't understand where you get 5m from? is it 8-3? but what are you working out when subtracting these values?

Original post by kittymityyy

thank you for your reply! :smile:

but i don't understand where you get 5m from? is it 8-3? but what are you working out when subtracting these values?

It’s to get rid of the decimal of *0.2n* you times it by 5 so it just becomes n and the top is 5m

It’s to get rid of the decimal of *0.2n* you times it by 5 so it just becomes n and the top is 5m

thank you so much! life saver! :biggrin:

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ratio and percentages in algebra *help* URGENT