<p>The</a> Official SAT Question of the Day . This one.
The answer doesnt make sense to me: Why does b/c=7 means that b/ (b+c)= 7/8?</p>
<p>yeahh i had problems with that too. i mean it works when you plug numbers in but im not sure how you’d know that…</p>
<p>I just think of it as <a b=“21/7” ==“” 3=“”> and <b c=“7/1”>. It just sorta came naturally.</b></a></p><a b=“21/7” ==“” 3=“”><b c=“7/1”>
<p>(21 + 7)/(7+1) = 28/8 = 7/2</p>
</b></a>
<p>Since b/c = 7. c/b = 1/7 Then adding one on both sides, c/b + 1 = 8/7 </p>
<p>–> common denominator yields (c+b)/b = 8/7 . Taking the reciprocal, we get (b)/(b+c) = 7/8.</p>
<p>Plugging in numbers would be easier, however.</p>
<p>Plug-ins saved me!</p>
<p>Their explanations revealed a simple method but that didn’t come to my head when I was working the question.</p>
<p>this is long. But this is how I did it lol.</p>
<p>a/b= 3 and b/c= 7</p>
<p>a/3=b b/7= c</p>
<p>Solve for: a+b/b+c </p>
<p>solve the problem in terms of a. Straight algebra lol. But I personally liked violins method.</p>
<p>I did what violin325 did. plug-ins are great when they are quicker than the ‘proper’ way of doing it</p>
<p>i did the same thing as violin. though not quite plugging in. i said that b/c=7 so it could be 7/1. that means that a/7=3 which makes a 21. so 21/7=3 and 7/1=7. then just add 21+7=28 over 7+1=8. 28/8=7/2</p>
<p>??? what???</p>
<p>I’m so confused. I understand Violin’s way, but will that always work?</p>