Problem Solving (PS) | Re: A store sells a certain product at a fixed price per unit. At the prod

Tough question. Need to deal with 3 equations.

I will try to explain it in a simple way:

Let's assume the article price is "P".

As per Question stem, Pq= $300..... equation 1

Also, if price is reduced by $5, quantity will increase by 2n; (c-5) * (q+2n) = $300 ..... equation 2
Again, if price is increased by $5, quantity will decrease by n; (c-5) * (q-n) = $300 ..... equation 3

Equaiton 2= Equation 3; we will get 2cn-5q-10n= 0 (by solving eq 2) & cn-5q+5n=0 9by solving eq 3)

Subtract
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