Last Christmas i was given a money box. The deal was if i can fill it up by next Christmas with obviously real money I would get a $1,000 bonus so i thought how would I go about using the least amount of money to fill up the money box. The following mesaurments are all in metric

The money box dimensions are 340mm high by 200mm wide. To work out the volume of the money box i did the following

200 / 2 = 100mm (Radius) x 3.14 = 3140mm (area) x 34 = 106,760 (volume)

I believe this is right however correct me if im wrong please

The next stage was how many 5 cent pieces can fit into that amount (i understand it would not be exact but im not looking for exact just a there about number)

the 5 cent piece is 19.41mm wide by 1.3mm thick So i worked out the volume as before

19.41 / 2 = 9.705 (radius) x 3.14 = 30.47mm (area) x 1.3 = 39.62 (volume)

So i worked out that to fill up the money box with 5 cent pieces i would do the following

volume of money box (106,760) / Volume of coin (39.62) = 2,695 coins

therefore to put a $1 value to this i would only need

2,695 * 0.05 = $134.75c of 5 cent pieces to fill up the money box.

Is this maths correct because it doesn't seem like that amount of money would fill up this money box.

Thanks

Chris