Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×
Math

Journal pythorlh's Journal: Basic math Question 17

Journal by pythorlh

I should know better, but I tried to have a discussion on another site today, and got accused of poor basic math skills. Being generally thick skinned, I shot right back, but the other person insisted on being wrong. Can someone answer a question for me?

So imagine that each person has three kids on average.

Given this, would anyone care to tell me how many siblings an average child has? Assume for the moment all children survive.

This discussion has been archived. No new comments can be posted.

Basic math Question More

Basic math Question

Comments Filter:
  • Since some families can have only one parent, families could consist of either 3 or 6 children. However, lets assume that half of the families have one parent; that would give us an average of 4.5 children per family, so the average would be 3.5 siblings. The sad part is most of the children will be orphans, since the parents of families with only .5 children in them will be sent to jail fairly quickly.
    • A family may consist of either 1 parent or two, but I'm pretty sure it requires 2 to have children. Barring artificial insemination anyway. I'm specifically talking about biological children here, not necessarily family children. Still, the person I was talking with insists that if each person averages 3 children, then each child averages 2 siblings. You at least noticed the problem. Even after explaining twice, this person did not.
  • How many such families overlap?

    if A has 3, and b has 3, and they are the SAME THREE KIDS, that's very different than each PERSON having three kids.

    You don't have poor math skills. Math begins by identifying the actual question.

    They have poor logic skills.

    • Comment removed based on user account deletion
      • Each person having three kids is not the same as three kids per parent.

        If you have three kids and your wife has (the same) three kids, each of you has three kids. Now if you said that about just the two of you, people would probably assume it meant six total (because it's an unusual way to state it if you're talking about one couple), but if you're in a room of parents, and someone said "each of these people has three kids," it would be perfectly fine.

        And the original question is even more amibiguous becaus
        • All of this is important if you're talking about a particular family or child, but the question talks about "on average". You find the average by counting all the children, and dividing by the total number of parents. Anything else isn't an average.

          Thus, any child has two parents, his two parents each average 3 children, and thus there are 5 siblings. They may be 4 half siblings and 3 full siblings, but again, since we're taking an average, all of that gets weeded out.

          • Okay. But I still say the question is ambiguous on the part about each person having three kids.
            • I'm not really arguing that it's not ambiguous. Just explaning that while it might be your first reaction to say 2, it's just as logical to say 5. In my mind, it actually makes more sense to say 5. In your mind it might make more sense to say 2. That's fine. Arguing that either of us is lacking basic math skills because of those answers would be the mistake.
    • My point exactly. The thing is he didn't just say that each person has three kids. He said "on average." It's the average bit that I looked at. I have 4 boys, and so does my wife, but my wife and I average 2 children per person. When people start using math language, I get very technical, because that's what math language is for.
  • One of the reasons why both my coding and writings attempts suffer is that I tend to generalize. The question uses "Person" instead of "Family," but I didn't pick up on it right away. I just looked at it, said 2, and wondered wherein the stuidity lied. Contextually the question is being answered for one of two purposes, to provide a simple math question that requires only the smallest of algebraic problem solving, or a far more complex problem which is challenging you to consider the various permutations
    • And indeed, the idea of the generalisation makes perfect sense. Both I and the originator made the family assumption to begin with. The idiotic part is arguing after the confusion is pointed out that there is no confusion. You can honestly justify either 2 or 5 easily. What you can't justify, is saying that either 2 or 5 is absolutely wrong, and the person choosing that answer is lacking in math skills.

      For your benefit, the discussion was regarding the passing down of genes. If each child has 2 sibling

      • One thing my Liberal Arts education taught me, especially emphasized over the course of an 8 year legal career, is that just because there is no "right" answer doesn't mean that there aren't a lot of "wrong" answers. Since 2 or 5 could be right, then arguing about them is the wrong answer. Besides, everone knows that everyone has 1.5 kids and a hyena.
  • The number of siblings would be as few as two (both parents share the same three children) and as many as five (each parent had three from a different relationship, married, and adopted the spouse's children).

    There is not enough information to provide a more accurate answer.

    (Oddly, Math was one of my best subjects in school.)

Slashdot Top Deals

It's a naive, domestic operating system without any breeding, but I think you'll be amused by its presumption.

Close