How to use float numbers on BusyBox?

Question

I have little computer, MMnet1000 with BusyBox, and compiling anything on it is nightmare.

I want to do something simple like "0,5*2", but can't without additional software.

I tried "expr", "let", and just can't do any operation with float numbers.

Is there something I can do?

UPDATE --- Carl Norum

root@MMnet:/kafka# dc
-ash: dc: not found
root@MMnet:/kafka# busybox dc
dc: applet not found

Answer 1

busybox has dc built in. Here's a link to all of the documentation.

Answer 2

busybox should have awk.

awk 'BEGIN{print 0.5*2}'