17 {{ upvoteCount | shortNum }}
17 {{ upvoteCount | shortNum }}

A math puzzle...

by sylviad
14 replies
  • OFF TOPIC
    • |
Ok. I'm trying to figure out the percentage of increase.

If you have a picture 8 inches by 10 inches and you blow it up to 8 feet by 10 feet, what is the percentage of increase?

I think it's 100 - or it could be 1000.... d-d-don't do math.

Thanks.

Sylvia
  • Profile picture of the author Alexa Smith
    Banned
    It must be 144 times as big (that's 12 squared).

    If you measure both in square inches, one is 8 x 10 (80)

    The big one, also measured in square inches, is (8 x 12) x (10 x 12), isn't it? Because a foot is 12 times as long as an inch. And a square foot is therefore 144 times as big as a square inch?

    You can see, without working it out, that 8 x 12 x 10 x 12 has to be (12 x 12) bigger than (8 x 10).

    So, the big one is 144 times the area of the small one. That's 14,400% as big. It's an increase of 14,300%.
    {{ DiscussionBoard.errors[7192326].message }}
    • Profile picture of the author RyanEagle
      I tried to solve it but... I figured I just agree with this calculation :rolleyes:

      Originally Posted by Alexa Smith View Post

      It must be 144 times as big (that's 12 squared).

      If you measure both in square inches, one is 8 x 10 (80)

      The big one, also measured in square inches, is (8 x 12) x (10 x 12), isn't it? Because a foot is 12 times as long as an inch. And a square foot is therefore 144 times as big as a square inch?

      You can see, without working it out, that 8 x 12 x 10 x 12 has to be (12 x 12) bigger than (8 x 10).

      So, the big one is 144 times the area of the small one. That's 14,400% as big. It's an increase of 14,300%.
      Signature
      {{ DiscussionBoard.errors[7192387].message }}
    • Profile picture of the author sylviad
      Originally Posted by Alexa Smith View Post

      It must be 144 times as big (that's 12 squared).

      If you measure both in square inches, one is 8 x 10 (80)

      The big one, also measured in square inches, is (8 x 12) x (10 x 12), isn't it? Because a foot is 12 times as long as an inch. And a square foot is therefore 144 times as big as a square inch?

      You can see, without working it out, that 8 x 12 x 10 x 12 has to be (12 x 12) bigger than (8 x 10).

      So, the big one is 144 times the area of the small one. That's 14,400% as big. It's an increase of 14,300%.
      Oh, my goodness.That's deep.

      What I did was take 10 feet and multiplied it by 12" for a total of 120" on one side.

      Next I multiplied 120 inches by 100% and only got 120, so I figure 100% would be wrong. Or would it be 120 times bigger?

      ...and that's where I got lost.

      As you can see, I haven't a clue re math.

      But I also figured, since the numbers are the same and only the feet/inches differed, it should be an easy 100% or 1000%. Somehow, going to square feet doesn't make sense to me. Not that you're wrong... in fact, you 're probably right. Logically, it's over my head. :rolleyes:

      Sylvia
      Signature
      :: Got a dog? Visit my blog. Dog Talk Weekly
      :: Writing, Audio Transcription Services? - Award-winning Journalist is taking new projects. Warrior Discounts!
      {{ DiscussionBoard.errors[7192462].message }}
    • Profile picture of the author daddykool
      Originally Posted by Alexa Smith View Post

      It must be 144 times as big (that's 12 squared).

      If you measure both in square inches, one is 8 x 10 (80)

      The big one, also measured in square inches, is (8 x 12) x (10 x 12), isn't it? Because a foot is 12 times as long as an inch. And a square foot is therefore 144 times as big as a square inch?

      You can see, without working it out, that 8 x 12 x 10 x 12 has to be (12 x 12) bigger than (8 x 10).

      So, the big one is 144 times the area of the small one. That's 14,400% as big. It's an increase of 14,300%.
      Spot on and 100% correct... and that was the hard way of doing it Alexa!

      The same equation can be applied and deemed to any physical merit measurement
      Signature
      LAUNCHING VERY SOON > PRE-REGISTER NOW FOR A WSO THAT EVERY WARRIOR NEW & OLD CAN MAKE $$$ FROM! LIMITED PRE-LAUNCH SPACES - PM or email: JVSuperstars@gmx.com TO RESERVE A PLACE & LOCK IN A SUPER LOW LIFETIME PRICE! *** NEVER TO BE REPEATED PRICE ONLY AVAILABLE ON THE WARRIOR FORUM & OUR VERIFIED JV AFFILIATE PROVIDERS! ***
      {{ DiscussionBoard.errors[7192486].message }}
      • Profile picture of the author sylviad
        Thanks everyone for your input.

        I honestly don't know who is correct. Someone just told me it would be 1100% increase. Here are his numbers:

        First begin by changing feet to inches so 8' x 12 = 96

        Now subtract the original amount from the maximum amount so 96 - 8 = 88

        Now divide the increase by the original amount so 88 / 8 = 11

        Now multiply by 100 to get a percent so 11 x 100 = 1100% increase.

        If you do the same for the 10 inches, you should also come out with 1100%

        To check: Multiply the original amount by the percent increase so 8 x 1100 = 8800

        Now divide by 100 so 8800 / 100 = 88

        Add the increase to the original amount so 8 + 88 = 96

        Divide 96 inches by 12 to get feet so 96 / 12 = 8'
        Signature
        :: Got a dog? Visit my blog. Dog Talk Weekly
        :: Writing, Audio Transcription Services? - Award-winning Journalist is taking new projects. Warrior Discounts!
        {{ DiscussionBoard.errors[7192594].message }}
        • Profile picture of the author Alexa Smith
          Banned
          Originally Posted by sylviad View Post

          Someone just told me it would be 1100% increase.
          This is wrong.

          But an obvious/easy mistake to make.

          Effectively, he's multiplied the area by 12 (1200%) before deducting the original unit (100%) to produce the mistaken answer of 1100%.

          What he ought to have done is to multiply it by 12-squared (144).

          8 feet is clearly 1100% longer than 8 inches. That's one-dimensional, though. For two dimensions (area rather than length) you have to deduct the one from 12-squared, not from 12. That leaves 143, or 14,300% as large.

          All you need is a calculator to verify this for yourself, Sylvia. How many "square inche pieces" do you need to cover a surface that's 8" by 10" (clearly 80, isn't it?). And how many to cover a surface that's 96" by 120" in size? Clearly 96 x 120, isn't it? That's 11,520 square inch pieces, rather than 80. And how much bigger than 80 is 11,520? Just divide one by the other, and the answer's 144, as it has to be.

          So one is 144 times the size of the other. And 144 times the size is 143 times bigger, of course. Multiply that by 100% and you have the percentage answer you asked for, 14,300%. No mystery here, folks ...
          {{ DiscussionBoard.errors[7192650].message }}
          • Profile picture of the author MissTerraK
            I'm going to go lay down now as just reading this thread has put my head to spinning.

            As a matter of fact, while laying down, I'm going to keep one foot securely on the floor.

            Ha! I'm obviously not a numbers girl either, sylviad.

            Terra
            {{ DiscussionBoard.errors[7192680].message }}
          • Profile picture of the author sylviad
            Originally Posted by Alexa Smith View Post

            This is wrong.

            But an obvious/easy mistake to make.

            Effectively, he's multiplied the area by 12 (1200%) before deducting the original unit (100%) to produce the mistaken answer of 1100%.

            What he ought to have done is to multiply it by 12-squared (144).

            8 feet is clearly 1100% longer than 8 inches. That's one-dimensional, though. For two dimensions (area rather than length) you have to deduct the one from 12-squared, not from 12. That leaves 143, or 14,300% as large.

            All you need is a calculator to verify this for yourself, Sylvia. How many "square inche pieces" do you need to cover a surface that's 8" by 10" (clearly 80, isn't it?). And how many to cover a surface that's 96" by 120" in size? Clearly 96 x 120, isn't it? That's 11,520 square inch pieces, rather than 80. And how much bigger than 80 is 11,520? Just divide one by the other, and the answer's 144, as it has to be.

            So one is 144 times the size of the other. And 144 times the size is 143 times bigger, of course. Multiply that by 100% and you have the percentage answer you asked for, 14,300%. No mystery here, folks ...
            Ok. That makes sense too. I guess I'm not the only one who's mathematically challenged, eh Terra. LOL!

            Sylvia
            Signature
            :: Got a dog? Visit my blog. Dog Talk Weekly
            :: Writing, Audio Transcription Services? - Award-winning Journalist is taking new projects. Warrior Discounts!
            {{ DiscussionBoard.errors[7192736].message }}
          • Profile picture of the author alistair
            Originally Posted by Alexa Smith View Post

            This is wrong.

            But an obvious/easy mistake to make.

            Effectively, he's multiplied the area by 12 (1200%) before deducting the original unit (100%) to produce the mistaken answer of 1100%.

            What he ought to have done is to multiply it by 12-squared (144).

            8 feet is clearly 1100% longer than 8 inches. That's one-dimensional, though. For two dimensions (area rather than length) you have to deduct the one from 12-squared, not from 12. That leaves 143, or 14,300% as large.

            All you need is a calculator to verify this for yourself, Sylvia. How many "square inche pieces" do you need to cover a surface that's 8" by 10" (clearly 80, isn't it?). And how many to cover a surface that's 96" by 120" in size? Clearly 96 x 120, isn't it? That's 11,520 square inch pieces, rather than 80. And how much bigger than 80 is 11,520? Just divide one by the other, and the answer's 144, as it has to be.

            So one is 144 times the size of the other. And 144 times the size is 143 times bigger, of course. Multiply that by 100% and you have the percentage answer you asked for, 14,300%. No mystery here, folks ...
            Ok you know all of this but can you reverse park?
            {{ DiscussionBoard.errors[7192866].message }}
            • Profile picture of the author Alexa Smith
              Banned
              Originally Posted by alistair View Post

              Ok you know all of this but can you reverse park?
              If the space is big enough ...
              {{ DiscussionBoard.errors[7193631].message }}
  • Profile picture of the author zimo
    I think it's 144, but I'm horrible at math.
    {{ DiscussionBoard.errors[7192342].message }}
  • Profile picture of the author m4dcoder
    the percentage of increase is 960%
    Signature
    Learn WordPress Web Design easy way!
    {{ DiscussionBoard.errors[7192868].message }}
  • Profile picture of the author Brian John
    been a while since my college days but i think it can be solved using the following formula:

    ((S2 - S1) / S1) x 100%, where S1 is the original size and S2 is the new size.

    So, if S2 is 11520 sq in (96 x 120), and S1 is 80 sq in, then ((11520 - 80) / 80) x 100% = 14,300%

    (this of course is a percentage increase, as indicated by the number being positive)

    nice job alexa.
    {{ DiscussionBoard.errors[7193933].message }}

Trending Topics