To solve the elapsed time problems, we need to calculate the difference between the starting and ending times for each scenario. Let's go through each problem step by step.
Problem 1: 1 a.m. to 9 a.m.
- Starting time: 1 a.m.
- Ending time: 9 a.m.
- Elapsed time: \( 9 - 1 = 8 \) hours
-
Answer: 8 hours
Problem 2: 3:30 p.m. to 6 p.m.
- Starting time: 3:30 p.m.
- Ending time: 6 p.m.
- From 3:30 p.m. to 4 p.m.: 30 minutes
- From 4 p.m. to 6 p.m.: 2 hours
- Total elapsed time: \( 2 \text{ hours} + 30 \text{ minutes} = 2 \text{ hours } 30 \text{ minutes} \)
-
Answer: 2 hours 30 minutes
Problem 3: Half past nine in the morning to 7 p.m.
- Starting time: 9:30 a.m.
- Ending time: 7 p.m.
- From 9:30 a.m. to 12 p.m.: 2 hours 30 minutes
- From 12 p.m. to 7 p.m.: 7 hours
- Total elapsed time: \( 2 \text{ hours } 30 \text{ minutes} + 7 \text{ hours} = 9 \text{ hours } 30 \text{ minutes} \)
-
Answer: 9 hours 30 minutes
Problem 4: 7 a.m. to 7 p.m.
- Starting time: 7 a.m.
- Ending time: 7 p.m.
- Elapsed time: 12 hours (from 7 a.m. to 7 p.m.)
-
Answer: 12 hours
Problem 5: Five in the morning to half past four in the afternoon
- Starting time: 5 a.m.
- Ending time: 4:30 p.m.
- From 5 a.m. to 12 p.m.: 7 hours
- From 12 p.m. to 4:30 p.m.: 4 hours 30 minutes
- Total elapsed time: \( 7 \text{ hours} + 4 \text{ hours } 30 \text{ minutes} = 11 \text{ hours } 30 \text{ minutes} \)
-
Answer: 11 hours 30 minutes
Problem 6: 4:30 p.m. to 12:30 a.m.
- Starting time: 4:30 p.m.
- Ending time: 12:30 a.m.
- From 4:30 p.m. to 12 p.m.: 7 hours 30 minutes
- From 12 p.m. to 12:30 a.m.: 12 hours 30 minutes
- Total elapsed time: \( 7 \text{ hours } 30 \text{ minutes} + 12 \text{ hours } 30 \text{ minutes} = 20 \text{ hours} \)
-
Answer: 20 hours
Problem 7: Six in the morning to eight in the morning
- Starting time: 6 a.m.
- Ending time: 8 a.m.
- Elapsed time: \( 8 - 6 = 2 \) hours
-
Answer: 2 hours
Problem 8: Half past six in the morning to two in the afternoon
- Starting time: 6:30 a.m.
- Ending time: 2 p.m.
- From 6:30 a.m. to 12 p.m.: 5 hours 30 minutes
- From 12 p.m. to 2 p.m.: 2 hours
- Total elapsed time: \( 5 \text{ hours } 30 \text{ minutes} + 2 \text{ hours} = 7 \text{ hours } 30 \text{ minutes} \)
-
Answer: 7 hours 30 minutes
Problem 9: Five in the afternoon to six at night
- Starting time: 5 p.m.
- Ending time: 6 p.m.
- Elapsed time: \( 6 - 5 = 1 \) hour
-
Answer: 1 hour
Problem 10: 1:30 p.m. to 8 p.m.
- Starting time: 1:30 p.m.
- Ending time: 8 p.m.
- From 1:30 p.m. to 2 p.m.: 30 minutes
- From 2 p.m. to 8 p.m.: 6 hours
- Total elapsed time: \( 6 \text{ hours} + 30 \text{ minutes} = 6 \text{ hours } 30 \text{ minutes} \)
-
Answer: 6 hours 30 minutes
Final Answers:
1. 8 hours
2. 2 hours 30 minutes
3. 9 hours 30 minutes
4. 12 hours
5. 11 hours 30 minutes
6. 20 hours
7. 2 hours
8. 7 hours 30 minutes
9. 1 hour
10. 6 hours 30 minutes
\boxed{
\begin{array}{ll}
1. & 8 \text{ hours} \\
2. & 2 \text{ hours } 30 \text{ minutes} \\
3. & 9 \text{ hours } 30 \text{ minutes} \\
4. & 12 \text{ hours} \\
5. & 11 \text{ hours } 30 \text{ minutes} \\
6. & 20 \text{ hours} \\
7. & 2 \text{ hours} \\
8. & 7 \text{ hours } 30 \text{ minutes} \\
9. & 1 \text{ hour} \\
10. & 6 \text{ hours } 30 \text{ minutes} \\
\end{array}
}
Parent Tip: Review the logic above to help your child master the concept of time duration worksheet year 4.
