1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Pie chart/proportion question

  1. Nov 21, 2014 #1
    I have attached a screenshot of the question. The methodology and answer that makes sense to me is the following:

    29 (Total number of pupils) / 3 (Number of pupils who speak 3 languages) = 9.7 (1 d.p)

    The answer given:
    3 / 29 = 0.1 (1 d.p)

    Have a misunderstood the question here? Any help is greatly appreciated.

    Attached Files:

  2. jcsd
  3. Nov 21, 2014 #2


    User Avatar
    Gold Member

    Your method gives you how many times a class of 29 pupils can be divided up into sets of 3 pupils. That wasn't the question.

    Your answer gives 900+ percent. How do you get more than 100% of the class? Obviously you can't. The answer given in the figure is correct.
  4. Nov 21, 2014 #3


    User Avatar
    Gold Member

    Look at a simpler case.
    Four balls: red, green blue and yellow.
    What proportion are red?
    It wouldn't be total / red because that would give you 4.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook