Write a a fraction. 30: 48

Question

callisto · Answer

a:b = $\frac{a}{b}$
Can you try it now?

asnaseer · Answer

@Callisto are you sure, I was under the impression that:$$a:b=\frac{a}{a+b}$$

asnaseer · Answer

e.g. if you apples to pears in the ratio 3:4 then 3/7 of them are apples

klimenkov · Answer

Hm. You have to know what means the ":" sign. If it is devision, then @Callisto is right. If it is the ratio - @asnaseer.

asnaseer · Answer

I was taught that ":" means ratio

asnaseer · Answer

@ongmon what have you been taught on this?

callisto · Answer

What I've learnt is the same as what has been taught in this video: http://www.khanacademy.org/math/arithmetic/basic-ratios-proportions/v/ratios-as-fractions-in-simplest-form

asnaseer · Answer

Hmmm - I've never come across it's usage in a context like that. See here for example: http://mathworld.wolfram.com/Colon.html

asnaseer · Answer

I guess the answer to this question depends on the response from @ongmon

callisto · Answer

In your example ''if you apples to pears in the ratio 3:4 then 3/7 of them are apples''
7 is the total number of fruit.
So, 3:7 is actually no. of apple: total no. of fruit

asnaseer · Answer

the way I was taught is as follows.
if the ratio of apples to pears is 3:4, then it means 3 out of every 7 fruits are apples, and 4 out of every 7 fruits are pears.

asnaseer · Answer

@ongmon please respond so that we can teach you in the method that is most suitable to how you have been taught.