10-Oct-02		G Drive 'Irr'
IRR Examples-- Student Loan to a Professor
Case A
Loan Amount			$1,000
Year
1			$1,200
	-$1,000 + $1,200/(1+irr)^1 = 0
	irr =	20%
Case B
Loan Amount			$1,000
Year
1			$0
2			$1,200
	-$1,000 + 0/(1+irr)^1 + $1,200/(1+irr)^2 = 0
	irr = sqrt(1.2) - 1	9.5%		1.095445
Case C
Loan Amount			($1,000)
Year
1			$200
2			$1,200
	-$1,000 + 200/(1+irr)^1 + $1,200/(1+irr)^2 = 0
Trial 1	irr = 15%
	-$1,000 + 200/(1.15) + 1200/(1.15)^2 = 0			173.913
				907.3724
	-1000 + 173.91 + 907.37 = 0
				1081.285
	-1000 + 1081 > 0
Trial 2	irr = 20%
	-$1,000 + 200/(1.20) + 1200/(1.20)^2 = 0			166.6667
				833.3333
	-1000 + 166.67 + 833.33 = 0
				1000
	-1000 + 1000 = 0	Q.E.D.