Question 1141468
m = s / c - 1
m%  = s / c * 100


m is the profit margin
c is the cost.


when s = 850 and m = .15, m = s / c becomes .15 = 850 / c - 1


add 1 to both sides of this equation to get 1.15 = 850 / c


solve for c to get c = 850 / 1.15 = 739.1304348.


when m = .20, the formula of m = s / c - 1 becomes .20 = s / 739.1304348 - 1


add 1 to both sides of this equation to get 1.20 = s / 739.1304348.


solve for s to get s = 1.20 * 739.1304348 = 886.9565217.


that's your solution.


to get 20% profit, your sale price needs to be 886.9565217.