Main content
Course: Precalculus (Eureka Math/EngageNY) > Unit 5
Lesson 2: Topic A: Lesson 2: Counting rules—The fundamental counting principle and permutationsCounting outcomes: flower pots
Find the number of ways you can put four types of flowers into three types of pots.
Want to join the conversation?
Is there an easier way to do this instead of having to write out the combonations every time?(34 votes)
You can just multiply them(76 votes)
At the beginning of the video would it have been easier to multiply at the beginning?(9 votes)
Yes, you could have, but Sal has to explain it as well in the video and show how it is a "mathematically legal," or correct, way to solve a problem. Also, he can't just say,"multiply 4*3 to get 12." That would result in an incredibly brief and short video. And there's no point in earning 850 energy points for watching a 4-second video.
; )(54 votes)
- Can't you just make a tree diagram?(8 votes)
Yes. This method is an alternative, but there are special situations where this method will be required and the same goes for using a tree diagram.(6 votes)
- Why does the counting principle work in telling how many different outcomes there could be for a specific situation in essence, and who came up with this principle?(2 votes)
The counting principle works by multiplying the number of options of one thing (pots) by the number of options for another (flowers). This basic form of counting works for practically any situation. It is just as simple using larger number as long as you remember: (Total options for A) (Total options for B)= (Number of ways to do A and B together). This basic principle has been around since the earliest days of math (the Romans were known to use pebbles to help with these problems) and there isn't a person on record who claims to have invented it. Once you get into the more advanced counting theorems, you do start to see some big math names, such as Carl Friedrich Gauss and Blaise Pascal, but they created individual theorems, not entire principles.(9 votes)
im am very dumb so I do not get this at all.(3 votes)
Why does he not just tell you the faster way, isn't that the idea of the video? To show you how to figure out these problems the easiest way possible?(1 vote)
No. the point of learning is to understand how to think about and solve these types of problems. Sometimes, this means considering several different approaches, not necessarily just the "fastest".(5 votes)
At2:00Sal shows how to find the number of combinations in-between flowers and pots. What about Multiple combinations, for example, to throw in 5 different designs you can add to the pots? How do you do that?
Or what about six-digit combinations to safes? How can you compute the number of possible combinations?
Please respond, because I have exams and really need these answers!(2 votes)- Thanks to the Counting Principle, you can find the total combinations by multiplying the number of choices for each slot.
For a six-digit combination safe, where each digit is chosen from the digits 0 to 9, you'll find ₁₀C₁ = 10 choices (ways to pick from ten things one at a time) for each of six slots.10∙10∙10∙10∙10∙10 = 10⁶ = 1,000,000 =
1 million total combinations for a 6-digit safe(2 votes)
this is kinda hard for a 5th grader do you have any tips(2 votes)- To get all possible outcome, just multiply the sum of possible outcomes in each category together. In the video, there were 4 flower types and 3 pot colors. So there were 12 possible scenarios because 4 * 3 = 12. But that always works. Say you’re going on a trip and you have to choose what clothes you are going to pack. If you have 10 pants, 15 shirts, 30 socks, and 3 pairs of shoes, the total of all possible outcomes you could get is 10 * 15 * 30 * 3 = 13500. If you’re rolling a pair of six-sided dice, the possible outcomes for one is 6. Multiply that by 6 for the other one, and the number of all possible outcomes is 36.
Hope that helps.(2 votes)
- i don't get anything that it is showing and im starting to get mad/stressed and when are we going to use this?(2 votes)
Well, it might be used for higher studies depending on what profession you choose. For example, weather forecasting, insurance, sports outcomes and even medical diagnosis.(2 votes)
So is this sort of like sample space?(1 vote)
2:00Video transcript
- [Voiceover] You're at a
florist store and you're interested in buying some
type of a potted flower. And you ask the florist, "What
type of flowers do you sell?" And he says, "Well we sell
four types of flowers, we sell "roses, tulips, sunflowers, and lilies." And you say, "What type of
pots could I put them in?" And he says, "Well you could
pick any flower, and then you "could pick any of our three
pots, we have brown pots, "we have yellow pots,
and we have green pots." So, the question that I ask to you is, how many types of, I guess,
flower and pots put together can you walk out of this florist store with? For example, you could get
a rose and a brown pot, you could get a rose and a green pot. Or you could get a yellow pot
that has a sunflower in it. Or a yellow pot that has a lily in it. So, how many scenarios could you walk out of that store with? And like always, I'll encourage
you to pause the video and try to figure it out on your own. Let's think through it. I'll just write the first
letters, just to visualize or just so I don't have
to write down everything. So, you could have a brown pot,
you could have a yellow pot, or you could have a green pot. You difinitely have to pick a
pot, so you're going to have one of those. And then for each of these
three, there's four possible flowers you could have. You could have a rose with the brown pot, you could have a rose with the yellow pot, you could have a rose with the green pot. You could have a tulip with the brown pot, a tulip with the yellow pot,
a tulip with the green pot. You could have a sunflower
with each of the three pots, or you could have a
lily with the brown pot, a lily with the yellow pot,
and a lily with a green pot. So, how many scenarios
are we talking about? Well, we had three pots, so
we have three pots right over here, and we have four possible
flowers to put in the pots, and so we see that we have
four possible flowers for each of the three pots. It's going to be three times
four possibilites, or 12. You see them right over here. This is brown with rose, brown with tulip, brown with sunflower, brown with lily. Yellow with rose, yellow with
tulip, yellow with sunflower, yellow with lily. So, if we count these, one,
two, three, four, five, six, seven, eight, nine, ten, eleven, twelve. Twelve possible pot, flower scenarios to walk out of that florist store with.