Is the answer in the CFAI books wrong here? Reading 6, Question 1

CFA Level I Quant
#1

Discounting each individual cash flow I get:

= -13 + 3/1.12 + 3/1.12^2 + 3/1.12^3 + 3/1.12^4 + 10

NPV = 6.13

Taking an annuity of four years I get:

= -13 + 3(1-(1.12^-4))/.12 + 10

NPV = -13 + 9.13 + 10

NPV = 6.13

However, the solutions say the NPV is 1.786. Why?

#2

If you are not using calculator, you need to discount each cashflow separately =-13+3/1.12+3/1.12 ^ 2 +3/1.12 ^ 3 +3/1.12 ^ 4 +10/1.12 ^ 5 =-13+2.78+2.39+2.14+1.91+5.67 =-13+14.89 =1.89 Think there are small approximation diff

#3

Why are you not discounting that final “+ 10”?

#4

Yeah, my bad. Thanks guys.