They have given justified leading P/E ratio as 14.1 and asking if stock is undervalued/overvalued/FairValued.

They way i did i calculated leading P/E ratio from the data given as 1-b/r-g = .72/.085-.034 = 14.11 and i thought its fairly valued. In the schweser answer explanation they are calculating trailing PE from income statement with detailed calculation as 14.1 and leading calculating trailing P/E from given value of leading P/E as 14.1*(1+.034) = 14.6 and hence concluding Stock is undervalued.

I am not understanding what I am doing wrong in my calculation or why do we need to calculate P/E ratio from income statement when they have given 3 values to calculate it directly.