How much is .50 cents?

I just noticed that Telstra’s web site shows excess data usage on their Data Pack 10 is $.050/Mb. Not quite sure what to make of that, I had a chat with Wendy, one of their on-line support agents:

Wendy 42164513: How may I help with your enquiry today?

Ben: Hi Wendy. I was just wondering if you could confirm the excess usage charges on the Data Pack 10 product. Your web site says $.050/MB, but I suspect it’s meant to say $0.50/MB

Wendy 42164513: .50c per meg Ben

Ben: so that’s half a cent, or 50 cents?

Wendy 42164513: thats correct Ben

Ben: which?

Ben: half a cent, or 50 cents?

Wendy 42164513: .50c Ben

Ben: .50c strictly means half a cent, but I find that very cheap. Are you sure?

Ben: the higher plans, for example, are 25c per meg

Wendy 42164513: Ben the cost is  fifty cents per meg, it has just reduced from 1.00

Ben: Thanks!

Wendy 42164513: You are very welcome Ben

Tiring!