Sonali started playing piano at =14:45
She start end playing it 45 min before starting her homework
She started doing her homework at =14:45+45=15:30(2:45 pm+45=3:30 pm)She finished doing her homework at 5:30pm
Time taken by her to finish doing her homework= 5:30 pm -3:30 pm =2:00 hrs
She takes 2hours to finish her homework.