<p>Can someone explain these:</p>
<p>1) Let A,B, and C be three points in a plane such that AB:BC = 3:5. Which of the following can be the ratio AB:BC</p>
<p>I 1:2
II 1:3
III 3:8</p>
<p>The answer is I and III. How is it also I?</p>
<p>2) Image</a> - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting</p>
<p>3) Image</a> - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting</p>
<p>Number 1 cannot possibly be written correctly. Check the question.</p>
<p>(2) John travelled for 1 hr 30 mins - 10 mins = 1 hr 20 mins = 1 1/3 hrs = 4/3 hrs. His total distance traveled was 5+5=10 miles. So r=d/t=10/(4/3) = 7.5 m/h, choice (B). </p>
<p>(3) The volume of the cylinder is V=pi<em>r^2</em>h =pi(8^2)(pi^2)=64pi^3
Since the cube also has this volume, an edge of the cube has length that is the cube root of 8pi^3. Thus it is 4pi choice (D).</p>
<p>(1) should read:</p>
<p>“Let A,B, and C be three points in a plane such that AB:BC = 3:5. Which of the following can be the ratio AB:AC”</p>
<p>ABC is a triangle or a straight line. So AC < AB + BC (triangle inequality) or AC = AB + BC if a straight line. Check to see if any of the choices violate both.</p>
<p>Choice I works. AB=3x, BC=5x, AC=6x – triangle</p>
<p>Choice II violates the triangle inequality and it is not a straight line. AB=3x, BC=5x, AC=9x. 9x>8x.</p>
<p>Choice III works. AB=3x, BC=5x, AC=8x – straight line.</p>
<p>Oops, sorry about that. It’s AB:AC</p>
<p>Anyways, thanks for the explanation guys =D</p>