Dave's ESL Cafe's Student Discussion Forums

[Marrion]

What is the real difference among "proportion", "rate" and "ratio"?

[alan.es]

A ratio is a comparison of two numbers. We generally separate the two numbers in the ratio with a colon. Suppose we want to write the ratio of 8 and 12.
We can write this as 8:12 or as a fraction 8/12, and we say the ratio is eight to twelve.



A proportion is an equation with a ratio on each side. It is a statement that two ratios are equal.
3/4 = 6/8 is an example of a proportion.


A rate is a ratio that expresses how long it takes to do something, such as traveling a certain distance. To walk 3 kilometers in one hour is to walk at the rate of 3 km/h. The fraction expressing a rate has units of distance in the numerator and units of time in the denominator.
Problems involving rates typically involve setting two ratios equal to each other and solving for an unknown quantity, that is, solving a proportion.

With thanks to the following site:

http://www.mathleague.com/help/ratio/ratio.htm

[Marrion]

May God bless you!!

[redset]

Those are quite mathematical definitions though, especially the proportion one. I don't know what context you're using those words in, but I'll try and give you some more general definitions too

Ratio is the amount or value of one thing compared to the amount or value of something else. In your class there might be a ratio of 3 females for every 1 male, which means if there are 6 females then there are 2 males, if there are 12 females then there are 4 males, and so on. There are three times as many females as males, no matter how many people there are in total. It gives you an idea of the balance between two things.

Proportion is similar to ratio, but it's used to talk about an amount compared to the total. If you spend 12 hours a day sleeping, 9 hours working, and 3 hours relaxing, then the proportion of your day spent sleeping is half. The proportion of a year that you spend asleep would be half too, because a proportion is the balance of one amount compared to everything else. If something's 'in proportion' then the amounts are all in the right balance.

Rate is how quickly something happens or changes - the faster the change, the higher the rate! You might also hear economists talk about 'the interest rate' and 'the rate of inflation', which are about how quickly the size of debts and the value of money change. There are also things like hotel rates, which is the cost of a room per night. You can think of these rates as a measure of how quickly your money disappears!

[Marrion]

Thank you very much, sir..^0^//