Cylindrical drums measuring 3 feet high and 2 1/2 feet in diameter are to be placed in a storage area. The floor of the storage area is a rectangle measuring 7 feet by 7 1/2 feet, and the drums cannot be stacked. What is the greatest number of drums that can be placed in the storage area?

dgfgrafgdfge111 Dec 9, 2018

#1**+2 **

Floor area of 1 drum =

pi * ( 1.25)^2 = 1.5625 pi ft^2 (1)

Total Floor Area = 7 * 7.5 = 52.5 ft^2 (2)

Number of drums that can be placed = (2) / (1) =

52.5 / [ 1.5625 pi ] ≈ 10 drums

CPhill Dec 9, 2018

#2**-1 **

I also got 10 in the same way, but for some reason the answer is 8. Do you know how?

dgfgrafgdfge111
Dec 9, 2018

#3**+2 **

I think it is because I didn't consider the space between the barrels....

Notice that......if we had 1 barrel....the actual area occupied by the barrel is a 2.5 x 2.5 square =

6.25 ft^2

So 52.5 / 6.25 = 8.4 barrels....( round to 8 barrels)

To get a feel for this....look at the following image :

CPhill
Dec 11, 2018