I see how they arrived at the answer of 1725 watts, and it is wrong. I don't see how you arrived at 1500 watts, but that is wrong too. I believe the correct answer is 1800 watts. Post #6 by Greg1707 offers the clue to the solution.
The rule is 150 watts for every 2 feet or fraction thereof. The test answer simply interpreted that as 150 watts per 2 feet. A 23 foot track equates to 11.5 sections of 2 feet each. Take 150 times 11.5 and you get 1725. Again, that is wrong.
If you were to build this track using only 2 foot sections, you would need 11 such sections to get the first 22 feet of track. Those 11 sections would be counted at 150 watts each, for a subtotal of 1650 watts. But then you need to cut a 2 foot section of track in half, to get the final length of 23 feet. That last 1 foot of track is to be treated as a "fraction of a 2 foot allowance," so it gets the full 150 watts assigned to it. Final answer, 1650 watts for the first 22 feet and 150 watts more for the last foot, for a total of 1800 watts.
Now, can you explain how you arrived at 1500 watts?
