Sal uses a recipe to explore equivalent ratios.
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- What if you have a number of guests like 20 guests coming over for your dinner party?(52 votes)
- when will we use ratios in real life, other than baking?(13 votes)
- like comparing prices per ounce while grocery shopping, calculating the proper amounts for ingredients in recipes and determining how long car trip might take.(2 votes)
- Thank you so much Sal! I learnt alot about ratios, I just have 1 question, can you teach us how to make them equal like if there were, lik, 19 people coming over?(14 votes)
- If you have 32 as the starting point, 1/2 and 1/4 are very natural ratios, but if you have 19 people, this a very awkward ratio of 19/32, so multiplying 19/32*8 = 4.75 makes it difficult to make a super cake with 3/4 of an egg. Or 10/32*6 = 3.5635 cups of flour. So if you have 19 guests, most people would tend to make the super cake that serves 32 and just expect to have leftovers.
Or they may say well what if I want to use 6 eggs which is 6/8 or 3/4 of each of the ingredients (3/4*32 = 24 people). 6*3/4 = 4 1/2 cups of flour and sugar or 2*3/4 = 6/4 or 1 1/2 cups of butter, etc.(10 votes)
- Does ratios work by what comes first like: 7 beach balls and 4 sand buckets, so would that mean the ratio is 7:4?(8 votes)
- yeah. it does depend on what comes first. if i was asked what the ratio of beach balls to sand buckets was, i could write "7:4" or "7 to 4"(3 votes)
- my teacher told me that order does not matter? How come?(4 votes)
- The order really does matter because if you have a problem like "For every 1 doughnut there is 3 cakes" your ratio can be 1:3, 2:6, 3:9. But if you notice the ratios I made was how many doughnuts there are first THEN how many cakes there are. Your teacher was probably confused or you were confused(4 votes)
- If you only have 16 people coming over then you should do half of the ingredients for the super cake!(8 votes)
- i dont really get some of these basic ratios but i know like 4:9 and stuff but like there saying your supooseto divide them(4 votes)
- I know i'm 2 years late but you can multiply and divide ratios. For example, the ratio 8:4. If you want to
multiply them by 4, you multiply each number by 4. So you get32:16. If you want to simply them, divide them by 4. So it's 2:1. Hope this helps for those who don't get it.(4 votes)
- Would you do the same if you tripled the recipe?(4 votes)
- i have 9 apple and 109 people.what is answer(4 votes)
- The ratio of apples to people is 9 apples for every 109 people. If you want to find an equivalent ratio to this just divide or multiply each side of the ratio by the same number.(4 votes)
- [Instructor] Right over here, we have the recipe for super cake, which you want to make for your guests that are coming over for dinner tonight. But this recipe right over here, this is for 32 people. This would serve 32 folks. But, you only have 16 guests coming over. So, if you only have 16 guests coming over, what should be your ingredients here? How much of each of these ingredients should you have? I encourage you to pause the video and think about it. Right now, we're gonna think about, well, we're gonna have a slightly smaller super cake. Smaller super, super cake. You might have reasoned that, "Look, if we're going to have half as many guests, "then each of the ingredients, "we should just have half as much." And you would be right. Instead of eight eggs, for our smaller super cake, you could have four eggs. Instead of six cups of flour, in our smaller super cake, you could have three cups of flour. Instead of six cups of sugar, you could have three cups of sugar. I'm just taking half of each of these numbers. Instead of two cups of butter, you could have one cup of butter. Instead of six teaspoons of baking soda, you could have three teaspoons of baking soda. And, last but not least, instead of two cups of water, you could have one cup of water. Now, this will work and this is actually how you should adjust recipes. But there's something interesting about what's similar about these two recipes. The recipe for the main super cake that feeds 32 people and the recipe for the smaller super cake. And that's the notion of ratios. The ratios between ingredients or the ratio of how much of an ingredient you need for given guests. For example, you can see here that for every eight eggs, you have six cups of flour. So, let me write this down. So, for every eight eggs we have six cups of flour. We have six cups of flour. Which can be expressed as a ratio of, the ratio of eggs to flour is 8:6. Which is, once again, interpreted as for every eight eggs, I have six cups of flour. If I said for every six cups of flour, I have eight eggs, I would've written 6:8. So, the order here matters. But here I'm saying the ratio of eggs to flour, of eggs to cups of flour is 8:6. For every eight eggs, I have six cups of flour. Well, what about for the smaller cake? Well, here, for every four eggs, for every four eggs, we have three cups of flour. We have three cups of flour. So, what would this ratio be? Well, for every four eggs, we have three cups of flour. So, the ratio of eggs to flour is 4:3. Now, turns out that these are the exact same ratio. If you have eight eggs for every six cups of flour, or for every eight eggs you have six cups of flour, that's the same thing as for every four eggs, you have three cups of flour. What you're just doing is taking each of these numbers and you are dividing it by two. So, you could say the ratio in either case, the ratio of eggs to flour, let me write this down. The ratio of eggs, eggs, to two cups of flour. Let me write two cups of flour. Cups of flour. In either case is, is four eggs for every three cups of flour. This is going to be true for either recipe. You have the same ratio. If you have eight eggs here, so, for every four eggs, you have three cups of flour. Well, that means your going to have six cups of flour. This is why ratios are helpful. This recipe has a different number of eggs, a different number of cups of flour, a different number of cups of sugar. But the ratios between the ingredients are the same. So, you will be able to have a cake that tastes the same, that essentially is the same cake but just is a different size.