Answer:
As the first payment occurs on option 7 n interest rate higher enough can make the 50 dollars received first make the difference.
The switch produced at a rate of :
300%
Interest rate below this mark favor option 6
while higher than this favor option 7
Explanation:
Option 6
perpetuity of 100 discounted 1.5 year
perpetuity of 50 every 3 years discounted 3 years
as the payment are every three years we calcualte an equivalent rate:
Option 7
perpetuity of 50 discounted 1 year
perpetuity of 100 every 2 years discounted 2.5 years
equivalent biannual rate
having the formulas
we can do it on excel solver to look at which rate the switch produces