The scenario described above is like dividing a right cone from the vertex down to the center for the base. The polygon that can be formed from the division or in this case slicing is a triangle. Thus, the answer to this item is letter B.
If 1/5 can for 1 (each) room, then: for 51 rooms, (51*1/5)=10.2 rooms. Round to nearest whole number since you can't just paint 0.2 of a room: answer = 10
You should use this app called photomath!! it will give you the answer to the equation and there is a show work option and if you press it, it will show the work for u :)