1. From 8:15 AM to 1:30 PM
add 45min to 8: 15 to give 9:00am
start the counting from 9am to 1 pm = 4 hours
1:00pm + 30 minute = 1:30pm
45min + 30 min = 75min = 1hour 15 min
4hours + 1hour 15 min = 5hours 15 minute
hence;
8:15 AM to 1:30 PM = 5 hours 15 minute
8. From 4:55 AM to 1:00 PM
add 5 min to 4:55 am = 5: 00 am
start counting from 5:00 am to 1:00 pm = 8 hours
5min + 8 hours = 8 hours 5min
Hence;
4:55 AM to 1:00 PM = 8 hours 5min
9. From 11:30 PM to 7:50 AM
start counting from 11:30pm to 7: 30am =8 hours
add 20 min to 7: 30 = 7 :50
8 hours + 20 min = 8hours 20 minute
Hence;
11:30 PM to 7:50 AM =8hours 20 minute