NPV Examiner’s Report

Hi all! can somebody please explain what I am missing here?

·A company is considering two mutually exclusive projects. The cash flows for each project are as follows:

Project X Year0 $ (15,000) Year1 $8,000 Year2 $8,000 Year3 $8,000
Project Y Year0 $ (15,000) Year 3 $26,000
The company evaluates projects using the net present value method and uses a cost of capital of 10%.
Which project(s) should the company undertake?
A Both projects
B Project X only
C Project Y only
D Neither project

So, I thought the correct answer was C. But instead of using the NPV factor for 10% in both projects. They use the NPV factor for one and the annuity factor for the other (I think). So this is the answer that they give:

The candidate therefore needs to
calculate the net present value of both projects:
NPV of X = ($15,000) + 2.487 x $8,000 = $4,896
NPV of Y = ($15,000) + 0.751 x $26,000 = $4,526
Note that in doing the calculation, I have used annuity factors, which are a valuable tool when
answering questions under exam time pressure, and yet this is a technique few candidates
generally use in Section B questions.

¿……?