Elapsed Time

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Elapsed Time · Grade 3 · Worksheet 2

1. Matiu starts his hike at 8:24 AM. He hikes for 2 hours and 46 minutes. What time does his hike end? Answer: 11:10 AM Solution: Add the hours: 8:24 AM + 2 hours = 10:24 AM. Add the minutes: 10:24 AM + 46 minutes. 24 + 46 = 70 minutes.
   Full step-by-step solution

   Step 1: Add the hours: 8:24 AM + 2 hours = 10:24 AM. Step 2: Add the minutes: 10:24 AM + 46 minutes. 24 + 46 = 70 minutes. Step 3: Since 70 minutes is more than 60, convert: 70 minutes = 1 hour and 10 minutes (70 - 60 = 10). Step 4: Add that extra hour: 10:24 AM + 1 hour = 11:24 AM, but we need to add only the 10 minutes from the conversion. So from 10:24 AM, add 46 minutes: 10:24 AM + 36 minutes = 11:00 AM, then + 10 more minutes = 11:10 AM. Final answer: 11:10 AM.

2. A rectangular city park is drawn with a length of 150 meters and a width of 80 meters. What is the total distance around the outside edge of the park? Answer: 460 Solution: A rectangle has 4 sides - 2 lengths and 2 widths The perimeter is the sum of all 4 sides Perimeter = length + width + length + width Perimeter = 150 + 80 + 150 + 80 150 + 80 = 230 230 + 150 = 380 380 + 80 = 460 The answer is 460 meters.
   Full step-by-step solution

   Step 1: A rectangle has 4 sides - 2 lengths and 2 widths Step 2: The perimeter is the sum of all 4 sides Step 3: Perimeter = length + width + length + width Step 4: Perimeter = 150 + 80 + 150 + 80 Step 5: 150 + 80 = 230 Step 6: 230 + 150 = 380 Step 7: 380 + 80 = 460 The answer is 460 meters.

3. 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. How many minutes was the bus ride? Answer: 75 Solution: There are 60 minutes in 1 hour The bus ride took 1 hour and 15 minutes Convert 1 hour to minutes: 1 × 60 = 60 minutes Add the additional 15 minutes: 60 + 15 = 75 minutes The bus ride was 75 minutes long
   Full step-by-step solution

   Step 1: There are 60 minutes in 1 hour Step 2: The bus ride took 1 hour and 15 minutes Step 3: Convert 1 hour to minutes: 1 × 60 = 60 minutes Step 4: Add the additional 15 minutes: 60 + 15 = 75 minutes Step 5: The bus ride was 75 minutes long

4. Start: 8:22 AM, End: 11:47 AM. How long? Answer: 3 hours 25 minutes Solution: From 8:22 AM to 11:22 AM is 3 hours (8:22 to 9:22 is 1 hour, 9:22 to 10:22 is 2 hours, 10:22 to 11:22 is 3 hours). From 11:22 AM to 11:47 AM is 25 minutes (47 - 22 = 25).
   Full step-by-step solution

   Step 1: From 8:22 AM to 11:22 AM is 3 hours (8:22 to 9:22 is 1 hour, 9:22 to 10:22 is 2 hours, 10:22 to 11:22 is 3 hours). Step 2: From 11:22 AM to 11:47 AM is 25 minutes (47 - 22 = 25). Step 3: Total elapsed time is 3 hours + 25 minutes = 3 hours 25 minutes. The answer is 3 hours 25 minutes.

5. Mere starts reading her book at 10:05 AM. She reads for 1 hour and 55 minutes. She imagines a number line showing the time from start to finish, with each hour marked. At what time does Mere finish reading? Answer: 12:00 PM Solution: Start time is 10:05 AM. The reading duration is 1 hour and 55 minutes. Add the 1 hour first: 10:05 AM + 1 hour = 11:05 AM.
   Full step-by-step solution

   Step 1: Start time is 10:05 AM. The reading duration is 1 hour and 55 minutes. Step 2: Add the 1 hour first: 10:05 AM + 1 hour = 11:05 AM. Step 3: Now add the 55 minutes: 11:05 AM + 55 minutes. Step 4: From 11:05 AM, add 55 minutes to reach the next hour. From 11:05 to 12:00 is 55 minutes (because 60 - 5 = 55). Step 5: So 11:05 AM + 55 minutes = 12:00 PM. The answer is 12:00 PM.

6. Aroha starts her baking class at 9:35 AM. The class lasts for 1 hour and 55 minutes. What time does the class end? Answer: 11:30 AM Solution: Start at 9:35 AM. Add 1 hour to get 10:35 AM. Add 55 minutes to 10:35 AM.
   Full step-by-step solution

   Step 1: Start at 9:35 AM. Add 1 hour to get 10:35 AM. Step 2: Add 55 minutes to 10:35 AM. 35 + 55 = 90 minutes. Step 3: 90 minutes is more than 60, so convert: 90 minutes = 1 hour and 30 minutes (90 - 60 = 30). Step 4: Add that extra hour to 10:35 AM: 10:35 AM + 1 hour = 11:35 AM. But wait—we already added the 1 hour from the minutes, so we need to adjust carefully. Better way: From 10:35 AM, add 55 minutes. 35 + 55 = 90 minutes. 90 minutes = 1 hour 30 minutes. So add 1 hour to 10:35 AM to get 11:35 AM, then subtract 60 minutes? No—let's redo clearly. Correct method: Start at 9:35 AM. Add 1 hour to get 10:35 AM. Then add 55 minutes: 35 + 55 = 90 minutes. 90 minutes = 1 hour and 30 minutes. So from 10:35 AM, adding 55 minutes means: 10:35 AM + 25 minutes = 11:00 AM, then + 30 more minutes = 11:30 AM. So the end time is 11:30 AM. Final answer: 11:30 AM.

7. Emma starts her art class at 9:15 AM. The class lasts for 1 hour and 45 minutes. What time does her art class end? Answer: 11:00 AM Solution: Start with the start time: 9:15 AM. Add the hours first: 9:15 AM + 1 hour = 10:15 AM. Now add the minutes: 10:15 AM + 45 minutes = ?
   Full step-by-step solution

   Step 1: Start with the start time: 9:15 AM. Step 2: Add the hours first: 9:15 AM + 1 hour = 10:15 AM. Step 3: Now add the minutes: 10:15 AM + 45 minutes = ? Step 4: 15 minutes + 45 minutes = 60 minutes, which equals 1 hour. Step 5: So, 10:15 AM + 45 minutes = 10:15 AM + 1 hour = 11:00 AM. Step 6: The art class ends at 11:00 AM. Final Answer: 11:00 AM

8. Aroha starts her hike at 9:47 AM. She hikes for 2 hours and 35 minutes. What time does she finish? Answer: 12:22 PM Solution: Start at 9:47 AM. Add 2 hours: 9:47 AM + 2 hours = 11:47 AM. Add 35 minutes to 11:47 AM.
   Full step-by-step solution

   Step 1: Start at 9:47 AM. Add 2 hours: 9:47 AM + 2 hours = 11:47 AM. Step 2: Add 35 minutes to 11:47 AM. 47 + 35 = 82 minutes. Step 3: 82 minutes is more than 60, so convert: 82 minutes = 1 hour and 22 minutes (82 - 60 = 22). Step 4: Add that extra hour to 11:47 AM: 11:47 AM + 1 hour = 12:47 PM. But wait—we need to subtract the 60 minutes we converted. Actually, from 11:47 AM, adding 35 minutes means: 11:47 AM + 13 minutes = 12:00 PM, then + 22 more minutes = 12:22 PM. Final answer: 12:22 PM.