Question

Seema finished her study at 2:30 P.M. she studied for 3 hours 50 minutes. so when did she started her studies.

Answer 1

Seema started her studies at 10:40 A.M.
After studying for 1 hour 20 minutes it was 12 noon.And after studying for another 2 hours and 30 minutes it was 2:30 P.M. So in total after 3 hours 50 minutes, she completed her studies.
Hope it helps

Answer 2

if Seema studied for 3:50 mins and completed studying at 2:30
Then she might have started studying at 10:40