mistake in may 2010 suggested answer of fm cap budgting

in may 2010 fm paper one question from cap budgting calculate npv discounted payback period and irr. 2 machine is given under consideration one life is 5 year and 2 ki life 6 year. This the mutually exclusive proposal. As per npv technique when mutually exclusive proposal is given and life of the proposal under consideration is nt same and both cash inflow and outflow is given than proposal having highes equvijant npv will be chosen bt in suggested only npv calculated nt equvilant npv plz help me ki kya main galat hun ya institute se mistake hui hai?