Math question, help!

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1

<p>I've been wrestling with this question for an hour! It's just bugging me now. </p>

<p>Can someone please explain it to me? I understand the question and it seems that I just don't know how to arrive at an answer. (Which is 20% btw.)</p>

<p>Someone please like make my night and show me? I'm helpless. </p>

<p>On a side note, don't get Grubers; too many mistakes and very vague explanations. </p>

<p>Thank you! </p>

<p><a href="http://i48.tinypic.com/2wd3n6d.jpg%5B/url%5D"&gt;http://i48.tinypic.com/2wd3n6d.jpg&lt;/a&gt;&lt;/p>

2

<ol>
<li>a = 1.1b. Also, ac = 1.32bd. If we substitute a with 1.1b, we get</li>
</ol>

<p>(1.1b)c = 1.32bd. Divide both sides by 1.1b</p>

<p>c = 1.2d</p>

<p>So if we let d = 100, then c = 120, for example. c is 20% greater than d.</p>

3

<p>We can write a is 10% greater than b and ac is 32% greater than bd as:
a=1.1b and ac=1.32bd
We can substitute a for 1.1b in the second equation to get:
1.1bc=1.32bd
Divide both sides by b to get…
1.1c=1.32d
Since you want to isolate c, just divide both sides by 1.1.
1.32/1.1=1.2
Therefore,
c=1.2d
which means c is 20% greater than d.</p>

<p>I hope this helped :slight_smile:
–ninja edit–
Looks like someone beat me to this xD whoops</p>

4

<p>You guys are incredible. Thank you thank you thank you! Times a billion zillion trillion!</p>

<p>However I have to go wallow in shame and misery now.</p>

5

<p>Vote for rspence</p>