Question 1048641
.
Jimmy and Dean were in a yacht race from Auckland to Suva, a distance of 1200km. Jimmy left port in Auckland two hours after Dean. 
He sailed at an average speed which was 2km/h faster than Dean and finished in Suva exactly one day before him.
Given that the average speed is distance/time then find Dean's average speed during the yacht race.
~~~~~~~~~~~~~~~~~~~~~~~~


<U>Solution 1</U>. One quadratic equation.


<pre>
Your governing equation is

{{{1200/v}}} = {{{1200/(v+2) + 2}}},

where "v" is the Dean's speed, in {{{km/h}}}.

Left side is the time Dean spent on his race. 
Think what is the right side.

Solve the equation for "v". As a first step, multiply both sides by n*(v+2)

The rest is arithmetic.
</pre>


<U>Solution 2</U>. Two equations in two unknowns.


<pre>
The governing equations are 

1200 = v*t,            (1)
1200 = (v+2)*(t-2).    (2)

These are the "D = RT" equations.

Again, "v" is the is the Dean's speed, in {{{km/h}}}.

"t" is the time Dean spent on his race. 

To solve it, express t = {{{1200/v}}} from (1) and then substitute it in (2).

Then solve for "v".
</pre>

For similar Travel and Distance problems see the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/travel/Travel-and-Distance-problems.lesson>Travel and Distance problems</A>  

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/travel/Wind-and-Current-problems.lesson>Wind and Current problems</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/travel/More-problems-on-upstream-and-downstream-round-trips.lesson>More problems on upstream and downstream round trips</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/travel/Wind-and-Current-problems-solvable-by-quadratic-equations.lesson>Wind and Current problems solvable by quadratic equations</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/NumericFractions/Using-fractions-to-solve-Travel-problems.lesson>Using fractions to solve Travel problems</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Unpowered-raft-moving-downstream-along-a-river.lesson>Unpowered raft floating downstream along a river</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Had-a-car-move-faster-it-would-arrive-quicker.lesson>Had a car move faster it would arrive quicker</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/travel/How-far-do-you-live-from-school.lesson>How far do you live from school?</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Selected-Travel-and-Distance-problems-from-the-archive.lesson>Selected Travel and Distance problems from the archive</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Selected-problems-from-the-archive-on-a-boat-floating-Upstream-and-Downstream.lesson>Selected problems from the archive on the boat floating Upstream and Downstream</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Selected-problems-from-the-archive-on-a-plane-flying-with-and-against-the-wind.lesson>Selected problems from the archive on a plane flying with and against the wind</A> 

in this site.


Also, you have this free of charge online textbook in ALGEBRA-I in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.


The referenced lessons are the part of this textbook (Travel and Distance problems of the section "Word problems").