Elapsed Time

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Elapsed Time · Grade 3 · Worksheet 1

1. Noah started his science homework at 10:16 AM. He worked on it for 1 hour and 51 minutes, then took a 16-minute break. After the break, he worked for another 36 minutes. What time did Noah finish his science homework? Answer: 12:59 PM Solution: Start time is 10:16 AM. Add the first work session of 1 hour and 51 minutes. 10:16 AM + 1 hour = 11:16 AM.
   Full step-by-step solution

   Step 1: Start time is 10:16 AM. Add the first work session of 1 hour and 51 minutes. 10:16 AM + 1 hour = 11:16 AM. Then add 51 minutes: 11:16 AM + 51 minutes = 12:07 PM (since 16 + 51 = 67 minutes, which is 1 hour and 7 minutes). Step 2: Add the break of 16 minutes to 12:07 PM. 12:07 PM + 16 minutes = 12:23 PM. Step 3: Add the second work session of 36 minutes to 12:23 PM. 12:23 PM + 36 minutes = 12:59 PM. Noah finished his science homework at 12:59 PM.

2. Liam's school field trip to the science museum started at 9:30 AM. The bus ride to the museum took 1 hour and 15 minutes. After spending 2 hours and 30 minutes at the museum, they returned to school, which took another 1 hour and 15 minutes. What time did Liam arrive back at school? Answer: 2:30 PM Solution: Bus ride to museum: 1 hour 15 minutes = 75 minutes Time at museum: 2 hours 30 minutes = 150 minutes Bus ride back: 1 hour 15 minutes = 75 minutes Total time = 75 + 150 + 75 = 300 minutes Convert 300 minutes to hours and minutes 300 minutes ÷ 60 = 5 hours exactly Add 5 hours to the starting time…
   Full step-by-step solution

   Step 1: Calculate the total time spent on the trip Bus ride to museum: 1 hour 15 minutes = 75 minutes Time at museum: 2 hours 30 minutes = 150 minutes Bus ride back: 1 hour 15 minutes = 75 minutes Total time = 75 + 150 + 75 = 300 minutes Step 2: Convert 300 minutes to hours and minutes 300 minutes ÷ 60 = 5 hours exactly Step 3: Add 5 hours to the starting time Starting time: 9:30 AM Add 5 hours: 9:30 AM + 5 hours = 2:30 PM Liam arrived back at school at 2:30 PM.

3. Lily's school field trip to the science museum started at 10:30 AM. The bus ride to the museum took 45 minutes. After spending 2 hours and 15 minutes exploring the exhibits, they took the same 45-minute bus ride back to school. What time did Lily return to school? Answer: 2:15 PM Solution: Start time is 10:30 AM Add bus ride to museum: 10:30 AM + 45 minutes = 11:15 AM Add time exploring exhibits: 11:15 AM + 2 hours = 1:15 PM, then + 15 minutes = 1:30 PM Add bus ride back to school: 1:30 PM + 45 minutes = 2:15 PM Lily returned to school at 2:15 PM
   Full step-by-step solution

   Step 1: Start time is 10:30 AM Step 2: Add bus ride to museum: 10:30 AM + 45 minutes = 11:15 AM Step 3: Add time exploring exhibits: 11:15 AM + 2 hours = 1:15 PM, then + 15 minutes = 1:30 PM Step 4: Add bus ride back to school: 1:30 PM + 45 minutes = 2:15 PM Step 5: Lily returned to school at 2:15 PM

4. A rectangular garden is drawn with a length of 85 meters and a width of 40 meters. What is the total distance around the entire garden? Answer: 250 Solution: We are asked to find the total distance around the entire garden. This means we need the perimeter of the rectangle. Perimeter = 2 × (length + width) Substitute the given values into the formula.
   Full step-by-step solution

   We are asked to find the total distance around the entire garden. This means we need the **perimeter** of the rectangle. Step 1: Recall the formula for the perimeter of a rectangle. Perimeter = 2 × (length + width) Step 2: Substitute the given values into the formula. Length = 85 meters Width = 40 meters Perimeter = 2 × (85 + 40) Step 3: Add the length and width. 85 + 40 = 125 Step 4: Multiply by 2. 2 × 125 = 250 Step 5: State the final answer with units. The total distance around the garden is 250 meters. ANSWER: 250

5. Lily started reading her book at 2:15 PM. She read for 45 minutes. What time did she finish reading? Answer: 3:00 PM Solution: Identify the starting time. Lily started reading at 2:15 PM. Identify the duration she read.
   Full step-by-step solution

   Step 1: Identify the starting time. Lily started reading at 2:15 PM. Step 2: Identify the duration she read. She read for 45 minutes. Step 3: Add the minutes to the starting time. 2:15 PM + 45 minutes = 2:15 + 45 min. Step 4: Break down the addition. First, add minutes: 15 minutes + 45 minutes = 60 minutes. Since 60 minutes = 1 hour, we convert the 60 minutes into 1 hour. Step 5: Add the 1 hour to the hours. 2 hours + 1 hour = 3 hours. Step 6: Combine hours and minutes. After adding, the time is 3:00 PM. Step 7: Final answer. Lily finished reading at 3:00 PM.

6. Sophia's family went on a hike at 9:55 AM. They hiked for 2 hours and 40 minutes before stopping for lunch. What time did they stop for lunch? Answer: 12:35 PM Solution: Start time is 9:55 AM. Add the 2 hours first: 9:55 AM + 2 hours = 11:55 AM. Now add the 40 minutes: 11:55 AM + 5 minutes = 12:00 PM (noon).
   Full step-by-step solution

   Step 1: Start time is 9:55 AM. Step 2: Add the 2 hours first: 9:55 AM + 2 hours = 11:55 AM. Step 3: Now add the 40 minutes: 11:55 AM + 5 minutes = 12:00 PM (noon). Step 4: Then add the remaining 35 minutes: 12:00 PM + 35 minutes = 12:35 PM. Step 5: Sophia's family stopped for lunch at 12:35 PM. Answer: 12:35 PM

7. Noah started his art project at 9:50 AM. He worked on it for 2 hours and 45 minutes before finishing. What time did Noah finish his art project? Answer: 12:35 PM Solution: Start time is 9:50 AM. First, add the 2 hours: 9:50 AM + 2 hours = 11:50 AM. Now add the 45 minutes to 11:50 AM.
   Full step-by-step solution

   Step 1: Start time is 9:50 AM. First, add the 2 hours: 9:50 AM + 2 hours = 11:50 AM. Step 2: Now add the 45 minutes to 11:50 AM. 11:50 AM + 10 minutes = 12:00 PM (noon). Step 3: Then add the remaining 35 minutes (45 - 10 = 35): 12:00 PM + 35 minutes = 12:35 PM. Noah finished his art project at 12:35 PM.