Is This a Bad Kids Maths Question?

This is a screenshot of a kids math question, I think it’s a terrible question as it doesn’t provide enough detail to definitely answer the question. My wife thinks it’s obvious as you can eye it. The answer agrees with her. I think it’s stupid.

What do you guys think is the answer and if it’s a good question.

https://files.ozbargain.com.au/upload/34092/118593/img_0860.…

Poll Options expired

  • 5
    Red
  • 1293
    Blue
  • 46
    Yellow
  • 23
    Equally likely

Comments

  • +108

    Very obvious BLUE. No need rocket science here nor Albert Einstein

    • +11

      Blue is about 50% of the circle, each yellow and red is about the same at 25%.

      • +1

        Agree with this logic.

        If you cut the circle into two halves, roughly top and bottom.

        2x blue + 1x red is greater than the bottom half
        yellow + 2x red is less than the top half

        Looking at the bottom half you can see there is more than 3x blue than red.

        If you then assume two half circles are close enough equal. Assumption being half with blue is at least as big as half with yellow.

        blue = half circle minus 1x red
        yellow = half circle minus 2x red

        Therefore more blue than yellow.
        Assumption also strengthens this difference.

    • +39

      Casinos were made for people like OP.

    • +1

      Equally blue or red due to gravity.

      • +1

        Gravity would not have effect if spinning on horizontal surface.

  • +22

    Question to check eyesight probable yeah. Question on maths, its stupid!

    • +12

      It is a maths question. The knowledge check here is to know that the longer the coverage of the parimeter, the more probable it is. So kids just need to take out thier tape measure and measure each color's total distance (testing addition with the red and blue). Then the longest answer is the answer.

      Also for the OP, just because you arnt able to do something doesnt mean it is stupid. Only stupid people think that way because they assume they know everything.

      • +6

        A protractor would be more accurate.

        • +7

          Yep, I measured it with a protractor.

          • Yellow: 100°
          • Blue: 85° + 85° = 170°
          • Red: 30° + 30° + 30° = 90°
      • +12

        There's a delicious irony in this comment in inferring other people are stupid while littering the response with an abundance of spelling, grammar and punctuation errors.

        • Not to mention, umm, tape measure? Good thing my kids always carry one of these around.

    • +1

      Question to check eyesight probable yeah

      Then it seems I'm colourblind. Can't see any colours other than shades of grey.

      • I see about 50

  • +21

    Uh, what more detail do you need for this?

    • +3

      How good looking op is compared to his wife.

      • +2

        Op needs to listen to his wife as she always rite ;-)

        • What about dads writes

  • +15

    One colour clearly take up more space than the others

  • +15

    if the chart is hung up on the wall and the spinner is loose, then it will point straight down (its starting position). Then what is the answer?

  • +16

    It's obvious that there is more blue than the other colours.

    I don't think it's a bad question as it requires a bit of thought to work out that you need to add the different areas together rather than just taking the single biggest area (which is yellow)

      • +6

        I think his thinking is perfectly acceptable.
        So equally likely.

        Teacher: Sir, please answer red blue or yellow according to the preset answers.

      • +38

        too subjective for a maths question.

        there is absolutely nothing subjective about it at all

        it's basic probability

      • +38

        So equally likely

        You're wrong.

        I think his thinking is perfectly acceptable

        Now you're both wrong…

        Think of it as a roulette wheel, it has 36 numbers on it instead of red and black and a single green it's laid out as follows;

        9 of these numbers are red, 10 of them are yellow, and the remaining 17 are blue.

        Now, tell me again… given those odds, what number are you going to place your bets on, the one with only 9/36 or the one with 17/36

        • +1

          Depends how much each one is paying.

        • Green “00”.
          2% of the time it wins every time

      • +2

        yikes

      • +8

        It makes use of estimation, logic and the understanding of a circle. Your kid used some poor logic skills in their estimation.

        The two blue make up slightly less than 50% of the circle. Yellow is 25%. You can automatically rule out the three being the same based on that alone, so your kid is missing a couple of key concepts from the get go. Red is maxing out at about 30% of the circle at that point, so it must be blue. Estimating that blue is smaller than yellow but there's two of them so they're the same is completely wrong. That's a spatial concept and it's not subjective at all. Yellow is 25% as it's a right angle. You don't have to be told numbers to estimate this.

        You mention below that your kid is in grade one, so I can see it being a reasonable attempt albeit wrong because it misses a couple of key concepts (at least he didn't pick yellow). If your kid hasn't been taught anything about right angles or percentages then it'd be a struggle, but I assume it comes after studying those concepts in class.

        Dunno why you think it's acceptable though, what are your math skills like?

          • +3

            @cloudy: Except it doesn’t change the answer. It’s close to a right angle, but even if it’s not then it needs to be a third for all three to be equal. It’s clearly not that big.

            But if it was a third, it and the two red pieces equal less than 50%, therefore it would make those two red pieces less than 16%. The last red piece is roughly the same size, so there’s no way it is getting up to 33%, so blue is still larger.

            It’s simple logic, you don’t need to know the sizes to estimate it, that’s the whole point. Walk through it a few times before worrying about the individual sizes.

            When you look at the two blue put together and the one yellow, do they look about the same size to you? Or do they look vastly different?

          • +9

            @cloudy: Are you… Are you… Deficient in some way? I'm genuinely not sure how anyone would get this wrong, unless they were in primary school.

            • +1

              @The Wololo Wombat: There is a small proportion of the population that will not be able to visualise this question as a spinning wheel in their 'minds eye'. A lack of spatial reasoning affects some with ADHD. They need to use frameworks to solve this, convert to numbers etc.

              These people can be otherwise very intelligent, like someone with colour blindness they probably don't realise they are deficient until they are tested

              • +1

                @greatlamp: I have aphantasia (if that's what you're referring to with the "mind's eye" comment) and I could still clearly tell it was blue by just looking

          • +1

            @cloudy: The yellow is clearly slightly more than right angle and the blue is clearly slightly less than right angle.

            You could make a poll on wether the yellow angle amount above 90° is more than the amount of blue under 90° and that would be a hard question.

            But that's not the point. With how close the two blue slices are to right angle it's pretty obvious that when added they will be:

            1. Bigger than right angle.
            2. Bigger than yellow, since yellow is just slightly above right angle.
            3. Almost taking half of the pie.
            • -3

              @lorikeet: You have said, its obvious…blue is bigger, along side with its clearly yellow is bigger than right angle.

              Yet in this thread there is people who sit in either side. Because this question is a matter of perception (for kids) I think it makes it a bad question.

              • @cloudy: Please quote any comment in this thread who failed to see that blue is the largest and whose username is not cloudy.

                You're right that it's a perception question, just not a hard one. Like knowing you don't put a round peg in a triangle hole also needs perception.

          • +3

            @cloudy: The exact percentages don't matter, blue has the largest area by far.

          • @cloudy: User name checks out, your thinking is not very clear. Hope your kids picked up more mum's genes

      • Unfortunately, your kid is just one of many kids who require more tutoring/teaching, it's pretty normal.

      • +1

        I'm glad your child has your wife there… I honestly struggle to understand how you still believe that your kid's answer is "perfectly acceptable". Nothing there is subjective, it's maths.

        Are you planning on teaching your child that "2 plus 2 equals 4" is discriminatory and subjective too?

      • What you can take away from this is that your wife should do all the math tutoring and you can watch tv instead. Hopefully your wife can get your kid to take after her.

  • +35

    the pecking order for intelligence in the household has been clearly established

    assuming where the spinner stops is completely random, blue has the largest area

        • -7

          Exactly where the question landed.

          So it's not suitable in other format but on a horizontal plane?
          That's the mistake

          • +4

            @Protractor: Sorry but no. The question is perfectly answerable in its current format regardless of the viewing mechanism.
            The blue sectors are very obviously close to 50% of the circle's total area, making the math (what little is required) farcically straightforwards.

            • @BinaryPirate: They are assuming the needle would rest at the 6 o clock position if the wheel was hung on a wall, biased by gravity. Then it wouldn't be an effective spinning wheel. A very odd take on the question

              • +1

                @greatlamp: Many of the assumptions on display in this thread reminds of the old adage, "If you make something idiot-proof, people will become better idiots".

            • +2

              @BinaryPirate: (1) The answer is blue, (2) the question is grey

  • +18

    I immediately said yellow but then realized there were two lots of blues and three reds. Not a bad question as it requires some analytical thinking.

    • +4

      Same here, if I was given 5 seconds to answer I probably would have got it wrong. 10 seconds and it was easy.

    • I said the same and had to read the comments here telling me there's another blue.

      This is why I often get questions wrong when there is more than one answer or an "all of the above" option.

  • +3

    what year is the child?
    Nothing wrong with the question?

    • +1

      You'd be worried if any kid in school couldn't answer this question.

  • +16

    It's extremely obviously blue, it's approximately 50% of the whole. Your wife is the smart one of the household.

      • +5

        And the size of the areas don't mean anything to you?

        So by your logic if I have 20 really thin but separate wedges, there's more chance the arrow will land on them over one big wedge covering half the circle?

      • +1

        When the username does not fit the comment

      • Some people don't appreciate sarcasm.

      • +2

        The purpose of this question is to allow the child to demonstrate their understanding of this exact distinction.

        The number of pieces of each color does not matter; the total area of each color is what the child should be focusing on.

      • Sad that people missed your joke 😭

  • +29

    Eh? Your wife is right. She's smarter than you. Listen to her more.

    • +6

      She's smarter than you

      That was the goal when looking for wife, some may say it was a low bar

      • +14

        some may say

        I believe you'll find that everyone is saying

        • -1

          I think you'd need to be a bit more explicit in this statement. Not sure OP is capable enough to read between the lines… (or circles, apparently)

  • +10

    It's more a spatial reasoning question- i.e. the ability to move and rotate shapes in your mind. Spatial reasoning is useful for geometry in mathematics and also very useful if you are a taxi driver. It improves a lot from 6yo to 12yo and so it's an appropriate question if the child is 12yo but not reasonable if they are 6yo. If your child can't do it but others the same age can then it may indicate that they need some help in this area.

    The question might also have been asked so the kids don't just think of mathematics as rote learning timetables and writing equations.

    • +4

      …you reckon a kid needs to be 12 years old to answer this question? 12 year old are doing linear algebra or geometry, not looking at colours on a pie chart.

      • -1

        12 year olds are doing Kronecker products?

    • If your child can't do it but others the same age can then it may indicate that they need some help in this area.

      Point me in the right direction, I’m clearly in the minority

      • +7

        Your kid not being able to do one question on a test is nothing to worry about. Tests add stress and stress makes you temporarily dumber than usual.

        If you want your kid to know the answer then get some scissors and cut the pieces out. Put the pieces side by side to see which colour is the largest or alternatively stack the colours on top of each other to see which is the largest area. Then do a similar problem but without scissors and ask your kid to image cutting out the pieces and putting them side by side/stacked.

        Spatial reasoning evolved for navigation, hunting prey and making tools. Do some similar stuff with your child. E.g. buy them a rubix cube, play jenga with them, let them navigate on the way to home/school or in a park/shopping centre. It also is used when moving liquids from one container to another. Make some cupcakes with your child and get them to estimate how many cupcakes can be made from one bowl of mixture.

        My dad taught me spatial reasoning when I was a kid. We're go to a random suburb and walk around and take note of where different cars were. Later that night we'd go back and he would start the siphon and then I had to transfer the petrol to larger containers and 3D stack them in the van.

        • Your comment stated out good and ended up Brilliant!

  • -3

    You're right that's insane.

  • +5

    Is This a Bad Kids Maths Question?

    poll options

    red, blue, yellow, equally likely

    No, it is a bad poll.

  • +4

    Depends… is the spinner vertical as in the diagram? Gravity would dictate that where it is now is where it would stop.

    Outside that, Blue is the answer, as it makes up almost half of the playing area. If this was a roulette wheel, I would bet Blue every spin. You wont win every spin, but your chances of landing on a blue section is a lot more than the other two.

    BUT!! because I am a NERD! I am going to work it out using maths… And some CAD work :D

    BRB!! nerds!

    • In theory, if you just had a ruler, you could calculate the width of the "pie pieces" at their widest point to determine relative size to the other pieces

      • +25

        Pfffft… not when I can just jam it into CAD and get the exact angles….

        Ok, so, layering this under a CAD drawing, I get the following.

        Each RED is 30 degrees. 30 x 3 = 90 degrees or 1/4 of 360 total. 0.25 or 25%
        The Yellow is 100 degrees. 100 degrees or 0.2777… or 27.8% a little over 1/4
        Each BLUE is 85 degrees. 85 x 2 = 170 degrees or 0.472… or 47.2%, a little under 1/2.

        Red = 25%
        Yellow = 27.8%
        Blue = 47.2%

        • +6

          Busy day?

          • +1

            @spackbace: 2 days before Christmas, oh yeah, we are flat out… 😂🤣

        • +3

          I don’t know what I expected but I can get on board with the dedication

        • Held a protractor up to the screen to get basically the same results.
          But, use the tools you have available to you. :)

        • Someone load the image to chat gpt and let's see how it goes

      • +12

        If you had scissors you could cut out each piece, roll pieces from each colour into a ball and then eat the balls. The colour with the most chew is the largest.

        • +3

          Yep, agree… Or, you could mentally eyeball the fact that if you "mentally" remove the bottom red piece and slide blue together it makes up almost 50% of the entire circle… :/

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