How to calculate IRR without higher rate of Interest given in the question? only lower rate is given in the question, can we assume any rate higher then the lower rate likewise if the lower rate is 10% given and examiner ask us to find out IRR?
You use any two rates of interest – the examiner need not give you any rates.
The answer will be slightly different depending which two rates you use, but this is because the relationship is not linear and does not affect the marks.
All of this is explained in my free lectures for both F9 and for F2, and you cannot expect me to type out all of my lectures here 🙂
The lectures are a complete free course for Paper F9 and cover everything needed to be able to pass the exam well.