Here are the solutions to the problems:
1) 7 hours 59 minutes + 3 hours 10 minutes
* Minutes: 59 + 10 = 69 minutes. Since 60 minutes make an hour, this is 1 hour and 9 minutes.
* Hours: 7 + 3 = 10 hours. Add the extra 1 hour from the minutes: 10 + 1 = 11 hours.
*
Answer: 11 hours 9 minutes
2) 19 hours 9 minutes – 1 hour 42 minutes
* Minutes: You cannot subtract 42 from 9, so borrow 1 hour (60 minutes) from 19 hours.
* 19 hours becomes 18 hours.
* 9 minutes becomes 69 minutes.
* Now subtract: 69 – 42 = 27 minutes.
* Hours: 18 – 1 = 17 hours.
*
Answer: 17 hours 27 minutes
3) 18 hours 6 minutes – 13 hours 25 minutes
* Minutes: Borrow 1 hour from 18 hours.
* 18 hours becomes 17 hours.
* 6 minutes becomes 66 minutes.
* Now subtract: 66 – 25 = 41 minutes.
* Hours: 17 – 13 = 4 hours.
*
Answer: 4 hours 41 minutes
4) 2 hours 38 minutes + 20 hours 33 minutes
* Minutes: 38 + 33 = 71 minutes. This is 1 hour and 11 minutes.
* Hours: 2 + 20 = 22 hours. Add the extra 1 hour: 22 + 1 = 23 hours.
*
Answer: 23 hours 11 minutes
5) 5 hours 40 minutes + 12 hours 52 minutes
* Minutes: 40 + 52 = 92 minutes. This is 1 hour and 32 minutes.
* Hours: 5 + 12 = 17 hours. Add the extra 1 hour: 17 + 1 = 18 hours.
*
Answer: 18 hours 32 minutes
6) 6 hours 17 minutes – 3 hours 27 minutes
* Minutes: Borrow 1 hour from 6 hours.
* 6 hours becomes 5 hours.
* 17 minutes becomes 77 minutes.
* Now subtract: 77 – 27 = 50 minutes.
* Hours: 5 – 3 = 2 hours.
*
Answer: 2 hours 50 minutes
7) Allen's Science Project (2 hours 15 minutes) + Art Project (3 hours 49 minutes)
* Minutes: 15 + 49 = 64 minutes. This is 1 hour and 4 minutes.
* Hours: 2 + 3 = 5 hours. Add the extra 1 hour: 5 + 1 = 6 hours.
*
Answer: 6 hours 4 minutes
Final Answer:
1) 11 hours 9 minutes
2) 17 hours 27 minutes
3) 4 hours 41 minutes
4) 23 hours 11 minutes
5) 18 hours 32 minutes
6) 2 hours 50 minutes
7) 6 hours 4 minutes
Parent Tip: Review the logic above to help your child master the concept of time subtraction worksheet.
