A clothing business finds there is a linear relationship bet
     A clothing business finds there is a linear relationship between the number of shirts,n.it can sell and the price.p, it can charge per shirt. In particular, historical data shows that 3000 shirts can be sold at a price of $59, while 5000 shirts can be sold at a price of S43. Give a linear equation in the form p - mn b that gives the price p they can charge for n shirts  
  
  Solution
n = number of shirts
 p = price of a shirt
 
 Since the relationship is linear and the equation is of the form:
 p=mn+b we will find m first. We have two values of p and two of m.
 They can be expressed as cartesian coordinates:
 
 (3000, 59) and (5000, 43)
 For our equation:
 (p2 - p1) = m(n2 - n1)
 (59 - 43) = m(3000 - 5000)
 m = (59 - 43)/(3000 - 5000)
 m = -16/2000
 m = -1/125
So the equation becomes:
 p = (-1n/125) + b
Now to find b. Use either point:
 59 = [-1*(3000)/125] + b
 b - 24 = 59
 b = 83 So the equation becomes:
 p = (-n/125) + 83

