How do you convert ratios to fractions?

I thought all you really had to do was change the colon to a forward slash, or you know put the first number over the second (unless you simplify as well). However, in this portion of my geometry class it's about finding a coordinate a certain portion of the ways on a number line. So like "Find the coordinate point that is 2/3 from A (2, 1) to B (5, 8)" and such. Anyway, the way they seem to be converting ratios to fractions is you add the two numbers together and the sum is the denominator and the first number remains the numerator. (continued)

Question

How do you  convert ratios to fractions?

I thought all you really had to do was change the colon to a forward slash, or you know put the first number over the second (unless you simplify as well). However, in this portion of my geometry class it's about finding a coordinate a certain portion of the ways on a number line. So like "Find the coordinate point that is 2/3 from A (2, 1) to B (5, 8)" and such. Anyway, the way they seem to be converting ratios to fractions is you add the two numbers together and the sum is the denominator and the first number remains the numerator. (continued)

anonymous · Answer

Have you heard of doing this? Is this correct?  In which case, is it correct that when translating 5:1 into a fraction it would be 5/6?

ganeshie8 · Answer

first of all, your understanding of ratios and fractions is correct :

5:1  is same as  5/1

5:1 is NOT same as 5/6

ganeshie8 · Answer

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