Educated Method Example Cost ($) Millions Sold 10 S 8.8 10 2.2 15 0.978 Millions Sold 20 0.55 25 1.352 30 D.244 35 0.18 5 10 15 20 25 30 35 40 Table 1: Collected Doto Cost ($) This is clearly an inverse relationship of some kind (as Cost increases, sales decrease) Cost*(-1) Millions Sold 10 J.2 8.8 0.1 2.2 Millions Sold 0.0667 0.978 0.05 0.55 1.04 0.352 0 0.0333 0.244 0.05 0.1 0.15 0.2 0.25 0.0286 0.18 Table 2: Modified Dato Cost*-1 ($*-1) Although closer to being linear, it is not, so we guess again Cost*(-2) Millions Sold 0.04 6.8 D.0 2.2 Millions Sold 0.0044 1.978 0.0025 0.55 0.0016 0.352 0.0011 0.244 0.0008 0.18 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 0.045 Table 3: Modified Dato Cost ^-2 ($*-2) This graph is linear. Therefore: Millions sold a Cost^-2 Millions sold = k Cost*-2 k = slope