TenMarks teaches you all you need to know about the basics of ratios.
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Ratios So in this problem it asks what is the ratio of right counters to yellow counters. So, when we talk about ratios, we’re talking about a comparison of two counts or measures that have the same unit. So when we’re talking about ratios, we’re talking about a comparison of two counts or measures that have the same unit. So to find the ratio of red counters to yellow counters, we count the number of red counters. So we know—we count our red counters which are two and then we count our yellow counters which is three. Now, the ratio of red to yellow counters is 2 red to 3 yellow counters. So the terms are two and three. Now, a ratio can be written in three different ways. So the first way that we can write a ratio is in words. Okay so we can write it in word form. So when we write it in word form, the ratio is 2 to 3, so we’d write it in. This is how it looks in word form, so the ratio is two to three. So every two red counters, there are three yellow. We can also write it as a fraction, so as a fraction it would be red to yellow, so it would be 2/3. We could also write it as a colon and the colon it would be written as 2:3. So these are different ways they can be written. So here are the three different ways that ratios can be written. Now, ratios can also be expressed in three different ways so we can express ratios in three different ways. So the first way is part to part. So, we can express ratios in part to part. The ratio of a red to yellow counter, so the ratio of red to yellow counter, so the ratio is 2 to 3. We can also do part to total. So the ratio of red to t7he total number of counters. So here we’re talking about the ratio of red to the total number of counters. So there are five counters in all, so the ratio would be 2 ratio red to the total number so it’s 2 to 5. Then we can also express a ratio in total to part. So when you do this, the ratio of the total red counters. So the ratio is 5 to 2, so it’s the total to the part. And these three ways are ways that we can express ratios. All right so things to remember and to keep in mind is that a ratio is a comparison of two counts or measures that have the same unit. Now, a ratio can be written in three different ways. It could be written in words, as a fraction or as a colon. A ratio can also—there are three kinds of ratios, we can express ratios three ways. So there are three different kind of ratios, a part to part ratio, a part to total ratio and a total to part.