Answer: False
Explanation:
This seems to me like a True or False question and the answer would be False.
Payback period is calculated on the basis of the timing of cash flows and since we do not know the useful life of Project B neither do we know the timing of it's cash flows, we cannot say for certain that Project A has a shorter Payback period.
For example, the initial investment could be $5 million for instance but Project A only pays $10 million on its 5th year whereas Project B had a useful life of 4 years and paid $2 million each of those years. Meaning it would have paid back before the end of the 3rd year.
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