Assume the exponential model has the form: y = a·eb·x Substituting (x,y) = (0,3681), 3681 = a·eb·0 3681 = a·(1) 3681 = a So we now know a, and can write: y = 3681·eb·x Substituting (x,y) = (1,5888), 5888 = 3681·eb·1= eb b = b = 0.469731927 Substituting (x,y) = (2,9422), 5888 = 3681·eb·2 = eb 2b = 2b = 0.9398629259 b = 0.4699314629 Both values of b round off the b = 0.470 So we will use 0.470 for b, and the formula y = 3681·eb·x becomes: y = 3681·e0.470x Now we substitute x=4 y = 3681·e0.470·4 y = 3681·e1.88 y = 24123.4514 Rounded to the nearest whole number, y = 24123 Edwin