Solving a Ratio Problem with Three Variables












0












$begingroup$


A question that just popped in my head after reading an article:




If the radius of Planet X is 16% larger than that of Earth, and Planet X has 40% the radius of Planet Y, then what is the radius of Planet Y in terms of Earth radii?




I'm having trouble trying to figure this one out. How would we solve this one?



I understand we may have to define one variable in terms of another to get the desired result, but again, I seem to be failing miserably at it.










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  • $begingroup$
    I literally just realized that and removed it. You beat me to it!
    $endgroup$
    – TRX
    Nov 12 '15 at 4:07










  • $begingroup$
    Also, I have since reworded the problem accordingly.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:11
















0












$begingroup$


A question that just popped in my head after reading an article:




If the radius of Planet X is 16% larger than that of Earth, and Planet X has 40% the radius of Planet Y, then what is the radius of Planet Y in terms of Earth radii?




I'm having trouble trying to figure this one out. How would we solve this one?



I understand we may have to define one variable in terms of another to get the desired result, but again, I seem to be failing miserably at it.










share|cite|improve this question











$endgroup$












  • $begingroup$
    I literally just realized that and removed it. You beat me to it!
    $endgroup$
    – TRX
    Nov 12 '15 at 4:07










  • $begingroup$
    Also, I have since reworded the problem accordingly.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:11














0












0








0





$begingroup$


A question that just popped in my head after reading an article:




If the radius of Planet X is 16% larger than that of Earth, and Planet X has 40% the radius of Planet Y, then what is the radius of Planet Y in terms of Earth radii?




I'm having trouble trying to figure this one out. How would we solve this one?



I understand we may have to define one variable in terms of another to get the desired result, but again, I seem to be failing miserably at it.










share|cite|improve this question











$endgroup$




A question that just popped in my head after reading an article:




If the radius of Planet X is 16% larger than that of Earth, and Planet X has 40% the radius of Planet Y, then what is the radius of Planet Y in terms of Earth radii?




I'm having trouble trying to figure this one out. How would we solve this one?



I understand we may have to define one variable in terms of another to get the desired result, but again, I seem to be failing miserably at it.







ratio






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Nov 12 '15 at 4:07







TRX

















asked Nov 12 '15 at 4:02









TRXTRX

43




43












  • $begingroup$
    I literally just realized that and removed it. You beat me to it!
    $endgroup$
    – TRX
    Nov 12 '15 at 4:07










  • $begingroup$
    Also, I have since reworded the problem accordingly.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:11


















  • $begingroup$
    I literally just realized that and removed it. You beat me to it!
    $endgroup$
    – TRX
    Nov 12 '15 at 4:07










  • $begingroup$
    Also, I have since reworded the problem accordingly.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:11
















$begingroup$
I literally just realized that and removed it. You beat me to it!
$endgroup$
– TRX
Nov 12 '15 at 4:07




$begingroup$
I literally just realized that and removed it. You beat me to it!
$endgroup$
– TRX
Nov 12 '15 at 4:07












$begingroup$
Also, I have since reworded the problem accordingly.
$endgroup$
– TRX
Nov 12 '15 at 4:11




$begingroup$
Also, I have since reworded the problem accordingly.
$endgroup$
– TRX
Nov 12 '15 at 4:11










2 Answers
2






active

oldest

votes


















0












$begingroup$

Let $X$, $Y$ and $E$ be the radii of the two planets and Earth, respectively. Then



$X = 1.16E$



and



$X = 1.40Y$



Substitution gives you $1.16E = 1.40Y$



Solve that equation for $Y$ and you'll have the result that you're looking for.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    x is 16% larger, not 16% of total.
    $endgroup$
    – fleablood
    Nov 12 '15 at 4:15










  • $begingroup$
    It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:18










  • $begingroup$
    Easy enough to fix. I edited my post to reflect the new wording.
    $endgroup$
    – G. Allen
    Nov 12 '15 at 4:20






  • 1




    $begingroup$
    Shouldn't that be X = 0.4Y?
    $endgroup$
    – TRX
    Nov 12 '15 at 4:22



















0












$begingroup$

We have $X = 1.16E$ and $X= 0.4Y$.



Equating these we get $1.16E = 0.4 Y implies Y = frac{1.16}{0.4}E = 2.9E$.



So the radius of planet $Y$ is $2.9$ Earth radii.






share|cite|improve this answer









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    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

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    active

    oldest

    votes









    0












    $begingroup$

    Let $X$, $Y$ and $E$ be the radii of the two planets and Earth, respectively. Then



    $X = 1.16E$



    and



    $X = 1.40Y$



    Substitution gives you $1.16E = 1.40Y$



    Solve that equation for $Y$ and you'll have the result that you're looking for.






    share|cite|improve this answer











    $endgroup$













    • $begingroup$
      x is 16% larger, not 16% of total.
      $endgroup$
      – fleablood
      Nov 12 '15 at 4:15










    • $begingroup$
      It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
      $endgroup$
      – TRX
      Nov 12 '15 at 4:18










    • $begingroup$
      Easy enough to fix. I edited my post to reflect the new wording.
      $endgroup$
      – G. Allen
      Nov 12 '15 at 4:20






    • 1




      $begingroup$
      Shouldn't that be X = 0.4Y?
      $endgroup$
      – TRX
      Nov 12 '15 at 4:22
















    0












    $begingroup$

    Let $X$, $Y$ and $E$ be the radii of the two planets and Earth, respectively. Then



    $X = 1.16E$



    and



    $X = 1.40Y$



    Substitution gives you $1.16E = 1.40Y$



    Solve that equation for $Y$ and you'll have the result that you're looking for.






    share|cite|improve this answer











    $endgroup$













    • $begingroup$
      x is 16% larger, not 16% of total.
      $endgroup$
      – fleablood
      Nov 12 '15 at 4:15










    • $begingroup$
      It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
      $endgroup$
      – TRX
      Nov 12 '15 at 4:18










    • $begingroup$
      Easy enough to fix. I edited my post to reflect the new wording.
      $endgroup$
      – G. Allen
      Nov 12 '15 at 4:20






    • 1




      $begingroup$
      Shouldn't that be X = 0.4Y?
      $endgroup$
      – TRX
      Nov 12 '15 at 4:22














    0












    0








    0





    $begingroup$

    Let $X$, $Y$ and $E$ be the radii of the two planets and Earth, respectively. Then



    $X = 1.16E$



    and



    $X = 1.40Y$



    Substitution gives you $1.16E = 1.40Y$



    Solve that equation for $Y$ and you'll have the result that you're looking for.






    share|cite|improve this answer











    $endgroup$



    Let $X$, $Y$ and $E$ be the radii of the two planets and Earth, respectively. Then



    $X = 1.16E$



    and



    $X = 1.40Y$



    Substitution gives you $1.16E = 1.40Y$



    Solve that equation for $Y$ and you'll have the result that you're looking for.







    share|cite|improve this answer














    share|cite|improve this answer



    share|cite|improve this answer








    edited Nov 12 '15 at 4:20

























    answered Nov 12 '15 at 4:12









    G. AllenG. Allen

    1564




    1564












    • $begingroup$
      x is 16% larger, not 16% of total.
      $endgroup$
      – fleablood
      Nov 12 '15 at 4:15










    • $begingroup$
      It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
      $endgroup$
      – TRX
      Nov 12 '15 at 4:18










    • $begingroup$
      Easy enough to fix. I edited my post to reflect the new wording.
      $endgroup$
      – G. Allen
      Nov 12 '15 at 4:20






    • 1




      $begingroup$
      Shouldn't that be X = 0.4Y?
      $endgroup$
      – TRX
      Nov 12 '15 at 4:22


















    • $begingroup$
      x is 16% larger, not 16% of total.
      $endgroup$
      – fleablood
      Nov 12 '15 at 4:15










    • $begingroup$
      It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
      $endgroup$
      – TRX
      Nov 12 '15 at 4:18










    • $begingroup$
      Easy enough to fix. I edited my post to reflect the new wording.
      $endgroup$
      – G. Allen
      Nov 12 '15 at 4:20






    • 1




      $begingroup$
      Shouldn't that be X = 0.4Y?
      $endgroup$
      – TRX
      Nov 12 '15 at 4:22
















    $begingroup$
    x is 16% larger, not 16% of total.
    $endgroup$
    – fleablood
    Nov 12 '15 at 4:15




    $begingroup$
    x is 16% larger, not 16% of total.
    $endgroup$
    – fleablood
    Nov 12 '15 at 4:15












    $begingroup$
    It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:18




    $begingroup$
    It was my mistake. G. Allen based this answer on the problem before I made an edit to it. Apologies.
    $endgroup$
    – TRX
    Nov 12 '15 at 4:18












    $begingroup$
    Easy enough to fix. I edited my post to reflect the new wording.
    $endgroup$
    – G. Allen
    Nov 12 '15 at 4:20




    $begingroup$
    Easy enough to fix. I edited my post to reflect the new wording.
    $endgroup$
    – G. Allen
    Nov 12 '15 at 4:20




    1




    1




    $begingroup$
    Shouldn't that be X = 0.4Y?
    $endgroup$
    – TRX
    Nov 12 '15 at 4:22




    $begingroup$
    Shouldn't that be X = 0.4Y?
    $endgroup$
    – TRX
    Nov 12 '15 at 4:22











    0












    $begingroup$

    We have $X = 1.16E$ and $X= 0.4Y$.



    Equating these we get $1.16E = 0.4 Y implies Y = frac{1.16}{0.4}E = 2.9E$.



    So the radius of planet $Y$ is $2.9$ Earth radii.






    share|cite|improve this answer









    $endgroup$


















      0












      $begingroup$

      We have $X = 1.16E$ and $X= 0.4Y$.



      Equating these we get $1.16E = 0.4 Y implies Y = frac{1.16}{0.4}E = 2.9E$.



      So the radius of planet $Y$ is $2.9$ Earth radii.






      share|cite|improve this answer









      $endgroup$
















        0












        0








        0





        $begingroup$

        We have $X = 1.16E$ and $X= 0.4Y$.



        Equating these we get $1.16E = 0.4 Y implies Y = frac{1.16}{0.4}E = 2.9E$.



        So the radius of planet $Y$ is $2.9$ Earth radii.






        share|cite|improve this answer









        $endgroup$



        We have $X = 1.16E$ and $X= 0.4Y$.



        Equating these we get $1.16E = 0.4 Y implies Y = frac{1.16}{0.4}E = 2.9E$.



        So the radius of planet $Y$ is $2.9$ Earth radii.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Oct 1 '18 at 9:11









        MRobinsonMRobinson

        1,759319




        1,759319






























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