 My Math Forum Help with a KA problem (Slope,speed, rate)

 Algebra Pre-Algebra and Basic Algebra Math Forum

 July 9th, 2017, 08:17 PM #1 Newbie   Joined: Jun 2017 From: North Texas Posts: 19 Thanks: 1 Help with a KA problem (Slope,speed, rate) -------- If the speed is constant why cant I divide the time by the distance of any of the entries instead of using the slope? July 9th, 2017, 09:09 PM #2 Senior Member   Joined: May 2016 From: USA Posts: 1,310 Thanks: 552 Because she did not start right away. She rode at a constant speed once she finished getting ready, but that means that her average speed was not constant from the time she got the call. It was only constant once she started pedaling. She could travel 5 km in 40 minutes after the call, giving an average rate of 0.125 km / min from the time of the call. She could travel 7 km in 52 minutes after the call, giving an average rate of about 0.135 km /min from the time of the call. So let's set it up as a system of equations. $\text {c = time spent cycling}.$ $\text {g = time spent getting ready}.$ $\text {t = total time}.$ $\text {r = constant speed while cycling}.$ $\text {d = distance traveled}.$ $\therefore d = 0 * g + c * r = cr$ because no distance is traveled during g. $\text {And } t = c + g \implies g = (t - c) \implies d = cr = (t - g)r = tr - gr.$ $7 = 52r - gr.$ $5 = 40r - gr.$ $\therefore 7 - 5 = (52r - gr) - (40r - gr) \implies 2 = 12r.$ What does that mean? It means she pedals 2 kilometers in 12 minutes. So how long does it take her to pedal 1 kilometer? Thanks from Rujaxso July 10th, 2017, 12:17 AM #3 Newbie   Joined: Jun 2017 From: North Texas Posts: 19 Thanks: 1 Triple dots = therefore and arrows means implies? right? I quoted your post to see but still getting the symbols down. July 10th, 2017, 01:03 AM   #4
Senior Member

Joined: Feb 2016
From: Australia

Posts: 1,849
Thanks: 661

Math Focus: Yet to find out.
Quote:
 Originally Posted by Rujaxso Triple dots = therefore and arrows means implies? right?
That is usually the case yes.

You should be able to quote this post and see,

$\therefore$,

$\implies$. Tags problem, rate, slope, speed Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Similar Threads Thread Thread Starter Forum Replies Last Post Chikis Elementary Math 25 January 31st, 2014 09:48 AM eddybob123 Physics 1 September 30th, 2013 07:40 PM MikeMJ Computer Science 3 June 26th, 2012 11:00 AM alikn Physics 3 October 30th, 2009 04:53 PM Kaitosan Calculus 0 April 27th, 2009 02:23 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top      