Well if you say you have a 10 Mbs down speed. Take the "10", and divide it by 10, and that's what you have in KB/s.
So technically you can download at 1MB/sec(1000KB/sec roughly).
The same concept for upload.
Since your connection is a 5Mbs connection, your top download speed should be somewhere around 500KB/sec.
Im sure you mean multiply
but yes, thats basically how it works.
the numbers just mean how much information can be received/sent at a time.
so if your service says 10Mbs/5mbs, that means you can download 10 Megabits per second and upload 5 Megabits per second.
Keep in mind that megaBITS are different from megaBYTES, 1 Byte=8 Bits.
So if you have 10Mbs/5Mbs means that you can download 800 Kilobytes per second, and upload about 400 kilobytes per second.
and yes, it can be very confuzzling.