Financial Equation HELP!?

Question

Project A
Year 0 = $-100,000
Year 1 = 32,000
Year 2 = 32,000
Year 3 = 32,000
Year 4 = 32,000
Year 5 = 32,000

Project B
Year 0 = $-100,000
Year 1 = 0
Year 2 = 0
Year 3 = 0
Year 4 = 0
Year 5 = 200,000

Required Rate of Return = 11%
What is each Projects...Payback Period, NPV & IRR?

Answer 1

Project A:
Payback period = Cost/Uniform annual benefit = 100000/32000 = 3.125 years
Using compound interest factor (11%):
NPV = -100000+32000(P/A,11,5) = -100000 + 320000(3.6959) =$18,268.80
IRR is found by setting PWd = PWr, where PWd is present worth of disbursements; PWr is present worth of receipts.
Then,
100000 = 32000(P/A, i*, 5) Find i* in table to make this equation true:
(P/A, i*, 5) = 100000/32000 = 3.125 and, from the tables, i = 18%
Project B:
Payback period: 5 years
NPV = -100000 + 200000(P/F,11,5) = -100000+ 200000(0.5935) = 18,700
IRR: 100000 = 200000(P/F, i*,5); (P/F, i*, 5) = 0.500, and i = 15%

Answer 2

A 3 1/16 years
16,458
18%

B 5 years
16,838
15%