# Textbook P349 simple calculation that confuses me!

Hi! I have 2 questions regarding this simple problem:

If I use my Texax Instruments BAII Plus calculator to enter the following: (under ordinary annuity mode)

N:19
I/Y: 7
PMT: 200,000
FV: 200,000 (actually the result is the same without entering the FV)

When computing PV, I get the result as 2,122,420.715. The textbook calculation for this step is 2,067,119.05. I understand the formula used in the textbook but I wonder why using the calculator yields a different result?

My second question isďĽša different approach will be viewing this as an annuity due (payment starting today of \$200000 for the next 20 years), so under the mode of â€śBGNâ€ť of the calculator, if we enter the following:

N:20
I/Y: 7
PMT: 200,000
FV: 200,000

Then when computing PV, I get the result of 2,318,802.849. But the textbookâ€™s result is 2,267,119.05. Iâ€™m totally lost!

Anyone can arrive at the same result as me? Any answer will be greatly appreciated!

I solved the calculation by replacing FV with zero for both â€śOrdinaryâ€ť and â€śDueâ€ť mode. But another question isďĽšif we go by the approach in the textbook, assume this is an ordinary annuity with 19 payments (only to add the first \$200,000 at the end),shouldnâ€™t the FV be \$200,000 instead of zero, as the 19th payment is \$200,000? Any thoughts? Thank you!

Problem solved again!

Explanation to the above question: as \$200,000 is already counted when â€śPMTâ€ť is entered as 19, so it shouldnâ€™t be counted again.

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