What formula should I use to solve the question

Question

In a political poll, 2/5 of  the respondents said they would vote for a certain candidate.  Of these, 1/3 were men.  What fraction of all respondents that voted were women?

Answer 1

  2         1        2         2       2         6        2        4
—— × —— = —— ;  —— – —— = —— – —— = ——
  5         3       15        5      15       15       15      15 

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If there is phrase "of these/this" you have to multiply.
For example: "There are 21 student in the classroom, 4/7 of these are girls. How many boys are in this class."
          4
21 × —— = 12 (girls)        
          7     
21 - 12 = 9 (boys)

Answer 2

Hi Beatrice, We don't really care about the number of people who aren't voting for the candidate. But we also know that 1/3 of THOSE who would vote are men. Therefore, we know that 2/3 of THOSE who would vote are women. Now, the question is, what is 2/3 of 2/5 (2/5 is the fraction of all respondents who would vote for the candidate)? We take (2/3)(2/5) = 4/15 This number (4/15) is the portion of all respondents who are women who are likely to vote for the the candidate. Side note: of course, there is also a fraction for the number of women who aren't likely to vote for him/her, but we don't care about that. Best of luck Beatrice!

Answer 3

Hey Beatice -- it appears that the "2/5" is the only part (R) we can look at: 1/3 of these were guys (M), and 2/3 were gals (W) ... of the 3/5 non-voters, who knows? The only other worthwhile calculation would be R*W= 2/5(2/3)= 4/15 of all were voting women ... Wish you well, ma'am :)