方案1:39*(P/A,i ,11)*(P/F,i,2)-200=0
设i=12%,39*5.9377*0.7972-200=-15.39
设i=10%,39*6.4951*0.8264-200=9.33
10 IRR 12
9.33 0 -15.39
(10-IRR)/9.33=(IRR-12)/15.39
IRR=10.75%
方案2:
20*(P/A,i ,11)*(P/F,i,2)-100=0
设i=12%,20*5.9377*0.7972-100=-5.33
设i=10%,20*6.4951*0.8264-100=7.35
10 IRR 12
7.35 0 -5.33
(10-IRR)/7.35=(IRR-12)/5.33
IRR=11.16%
因此应当选择方案2。