St of cash flows

Hello sir

I wish to ask a query in cash flows preparation

Pls find below a part of question from a study text…

In notes…
Fixture and fittings cost 85000 and NBV 45000, were sold for 32000 during the year

Accumulated depreciation for year1is 340 and Y2 is 290

In solutions

Working – Depreciation

Dep for y2 340
Dep for y1. 290
Dep on assets sold (85-45) (40)
Charge for the year (250)
Ans is 90

My query is …. pls let me know why is depreciation of sold asset(40) deducted (/added) in above calculations??

Loads of thanku for all ur lectures advice and time. I self study for exams… and ur lectures and advice is of great help and guide to me.
Thank u once again