Really quick and basic ratio question?

Test Preparation SAT Preparation
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<p>For Gruber's Complete SAT 2008, is there a typo for problem 32 on p.264?</p>

<p>Q: If P+Q=R, P+R=2Q, what is the ratio of P to R.</p>

<p>Both the book and I eventually get 3P=R. Now, the question is whether the ratio is 1:3 as the book says, or 3:1, which I think is more logical.</p>

<p>Also, found another typo? for problem 35 in the same section? If m+4n=2n+8m, what is the ratio of n to m? Is it 2:7 (what i got) or 7:2. I'm really worried because these questions are testing the same concept and are also the first typo that I've spotted doing the math sections.</p>

<p>Edit: Wow! Just got #45 in the same section wrong as well, and it's the same exact problem! So what am I doing wrong?</p>

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<p>Whenever I come across a ratio problem I just convert all the variables into a multiple of each other. So in the question, I would substitute R as 3P.</p>

<p>So the ratio of P : R = P : 3P = 1 : 3</p>

<p>7m = 2n, n = 7/2 m
The ratio of n : m = 7/2 m : m = 7 :2 </p>

<p>To avoid being confused, do not try to immediately guess the answer but logically put in the variables.</p>

<p>Hope this helps.</p>

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<p>You may also not be clear on the notation…</p>

<p>The ratio of x to y is the same as “x : y” which is the same as x/y …</p>

<p>So, when you found 3P = R, then P/R = 1/3, so that P : R = 1 : 3 …</p>