Question 796638
Assume n bicycles of each plan.
x = total cost for first plan;
y = total cost for second plan.


First plan: 125000+225n=x


Second plan:  100000+275n=y


We might want to know, for how many produced bicycles would the two plans be of equal cost.  Equate x and y, and solve for n.


We can use this found value of n to calculate which plan is more expensive for quantity of bikes less than n; and we can calculate which plan is more expensive for quantity of bikes greater than n.


Starting this, if {{{x=y}}}, then {{{125000+225n=100000+275n}}},
{{{125000-100000=275n-225n}}}
{{{25000=50n}}}
{{{2500=5n}}}
{{{n=500}}}.   This is how many bikes produced of each plan would make the plans equal in cost.


Now, you can test x and y for {{{n<500}}} and for {{{n>500}}} and see how the plans compare.
--
{{{x=125000+225*400}}}=?
-
{{{y=100000+275*400}}}=?, and the "400" is just arbitrarily chosen.
-
-
{{{x=125000+225*600}}}=?, and again, the "600" is arbitrary.
-
{{{y=100000+275*600}}}=?