Acrew ship has 148 rooms with fifty on each of the two upper decks and the rest on the two lower decks. an upper deck room cost $1,000 and the lower deck room costs $900. use the four-step plan to find the greatest possible room sales on one trip.

I'm not sure what your four step plan is, but here is how I would solve it:

50 rooms on each upper deck x 2 decks = 100 rooms

100 rooms x 1000 per room = 100,000

That leaves 48 rooms on the 2 lower decks, so 48/2=24 rooms per lower deck

48 rooms x 900 per room = 43,200

100,000 + 43,200 = $143,200 (maximum room sales amount)

Hope this helps!! :)