Okay thank you again for your replies. It wasn't a large rat it was a Medium according to the chart. (thank you Joci for posting that) 110 grams is what the thing said.

The weight of the snake was told to us when we got her, though we haven't weighed her so we don't know for sure. Cleo weighs 964 grams.

We will follow the chart and go with one small rat every 7 days.