Normal and Abnormal Losses

Hello sir,
I found a question on process costing quoting :
Input =1, 000kg
Normal loss =10%
Output =830kg

Then there was also 5% of weight loss in the process.
I failed to interpret the meaning of this 5% sir.
First thought it was actual loss but then actual output was already given and different to what I got.
My last thought was to add the 5% and 10% to have a new normal loss percentage.
Help me out please.