# Math Help - a wood is a circle or square?????

1. ## a wood is a circle or square?????

omg.. i dun understand tis question.. plz help~~

2. Originally Posted by xiaoz
omg.. i dun understand tis question.. plz help~~
Density is mass per unit volume, so we need to convert all the units involved
to a common base (metres and kgm), find the volume of the wood and divide
the mass by that volume.

The wood is 1.2m by 15cm by 3mm, or converting all to metres it is
1.2m by 0.15m by 0.003m. So the volume is 1.2x0.15x0.003=0.00054 cubic metres.

Now the mass of the wood is 340g, which is 0.34kg.

So the density is 0.34/0.00054=629.63 kg/cubic metre,
which is about 63% the density of water.

RonL

3. but y the ans says tis ?

4. Originally Posted by xiaoz
but y the ans says tis ?
Are you saying that the given answer is: $19.2m \le L < 20.5$?

If so I suspect that either there is a misprint or you are looking at the