<p>Barbara can grade t tests in 1/x hours. At this rate, how many tests can she grade in x hours?</p>
<p>A) tx
B) tx^2
C) 1/t
D) x/t
E) 1/tx</p>
<p>The answer is B. I'm really confused as to how one would get this answer.</p>
<p>barbara can grade T tests in 1/x hours. We can simply set up the equation and cross multiply, just as you would do for any problem that involves poroportion.</p>
<p>so </p>
<p>T per 1/x hours = T/1/x , which turns into tx/1 .
Which gives us the rate of her work.</p>
<p>Now, how many tests can she take in X hours? to find that, we multiply the rate and X</p>
<p>TX/1 x X = TX^2/1 = TX^2</p>
<p>B.</p>
<p>Hope that helps.</p>
<p>All right, thanks, I get it. how about this one?</p>
<p>If 500 pounds of mush will feed 20 pigs for a week, how many days will 200 pounds of mush feed 14 pigs?</p>
<p>A) 4
B) 5
C) 6
D) 7
E) 8</p>
<p>The answer is A.</p>
<p>500 lbs feeds 20 for 7 days.
That means 500 will feed 140 for 1 day, which means 50 will feed 14 for 1 day.
Since you have 200 lbs, it can feed 14 for 4 days.</p>
<p>20 pigs eat 500 in 7 days
1 pig eats 25/7 in 1 day
14 pigs eat 50 in 1 day
14 pigs eat 200 in 4 days.</p>
<p>A.</p>
<p>Thanks, it makes sense now. I'm having so much trouble with ratios, for some reason. Ugh.</p>
<p>If 3*a* = 2*b* and 3*b* = 5*c*, what is the ratio of a to c?</p>
<p>I got 9/10 but the correct answer is apparently 10/9. Help?</p>
<p>if 9A=10C , which one is bigger? Think about it.</p>
<p>Okay, that makes sense. If it were, say, 9A=35C, would the ratio be 35/9?</p>
<p>If it were 35A=9C, would it be 9/35? </p>
<p>Am I finally beginning to understand this?</p>
<p>Are you still referring to the A:C ratio? or the C:A? </p>
<p>Here, answer these two questions, and tell me how you got your answer.</p>
<ol>
<li>what's the ratio is A:B if 100B=A</li>
<li>What's the ratio of X:Y if 3Y=2X</li>
</ol>
<ol>
<li><p>The ratio would be 1:100 because there are 100 Bs for every A. </p></li>
<li><p>The ratio would be 2:3 because there are 2 Xs for every 3 Ys. </p></li>
</ol>
<p>That's how I think about ratio problems in my mind. I'm not sure if I'm right, though...</p>
<p>Ok you still don't get it lol. Don't worry, i had the same problem a few weeks back! </p>
<p>When we are looking for the ratio of A:B , we want A/B right? if A is bigger than B , the ratio will be bigger than 1! because if A is 2 and B is 1, then A:B = 2/1 , which is 2. Now i see where you get confused when it comes to these problems, because once you find the values of A and B, you immediately assume that the numbers in front of those letters must be their value. Take the 1st question i gave you for example.</p>
<p>We want the ratio of A:B, and 100B=A . You said that the ratio of A:B is 1/100. You're confused because you're thinking in a mathematical sense. You see A alone so you assume A must be 1 and since 100 is in front of B, it bmust be 100. Why is that not the case? I asked you earlier "which one is bigger"? If 100B=A, and we want the ratio of A:B , the ratio of 1/100 would imply that A is only 1/100 of B. Is A smaller or is B smaller? </p>
<p>Forget the numbers and letters, and ask your self. if 100B=A , would A be the bigger value or will B be the bigger value? We need 100 B's to equal A. If we need 100B to = A, then A is clearly the bigger value. So if we want the ratio of A : B, the ratio is clearly not 1/100 because that would imply A being the smaller value, which it isnt. Therefore you must reverse it.</p>
<p>A:B, if 100B=A, that means ONE A= 100 Bs , so that would be 100/1 .</p>
<p>Hope that clears things up.</p>
<p>Ohhh, okay. So for the second question you asked me, would it be 3/2?</p>
<p>Yes, it would be 3/2 . because im asking for the ratio of X:Y, and since 3y=2x, X is the bigger value.</p>
<p>If you still have a hard time understanding the concept. Just remmber to reverse the numbers each time your asked to find the ratio. </p>
<p>A:B, with 2A=6B . reverse it. 6/2.
Remember that and you'll be fine.</p>
<p>I'm starting to understand it better. Thanks so much.</p>
<p>One last thing, though. In the last example you gave, A is bigger than B, so the ratio of A to B must be greater than 1, so it's 6/2. However, if you were asking or the ratio of B to A, the ratio would be less than 1 because B is less than A. So it would be 2/6. Is all of that right?</p>
<p>So does this mean that you always have to reverse the numbers when you're asked to find a ratio?</p>
<p>Correct. You got it.
Do we always have to? only in those situations. If you were asked to find A:B, and you are told that A=35 and B=70 , then it would be wrong to reverse it because its obvious which would be which.</p>
<p>A:B is the same as A/B
B:A is the same as B/A</p>
<p>The value that comes first is the numerator. What the ratio is ultimately depends on what the Values of A and B are.
The ratio if A:B when A=2 and b=1 is 2 because 2/1=2 . Its like a constant.
the ratio of A:B when 2A=10B is 10/2.</p>