Question 1:

Chris arrived at the dentist's office at 2:50 in the afternoon; his appointment with the dentist was scheduled at 3:15 in the afternoon. How many minutes did he have to wait for the appointment?

Question 2:

Karen took the bus at quarter to nine in the morning, which was 30 minutes earlier than her usual bus. What time is her usual bus?

Question 3:

The musicians arrived at the concert hall at one minute past seven. After 25 minutes, they started rehearsing. What time did they start rehearsing?

Question 4:

If Dr. Johnson usually leaves at 6pm but his last appointment started at 5:15pm and took 45 minutes, how much later did he leave the office than usual?

Question 5:

Dr. Lee recommended the fourth patient to rest at home for 10 hours after his appointment. How many minutes did the patient have to rest?

Question 6:

The athletes started their training at 6:00am and took a water break at 8:20am. How long did they train before the water break?

Question 7:

Every day, the supermarket opens its doors at 9:00 in the morning. However, on a particular day, it opened at 9:30 in the morning. How much later did the supermarket open than its usual time?

Question 8:

Mary marinated the pork for 240 minutes. How much time (in hours) did she marinate the pork?

Question 9:

If each game takes 15 minutes to prepare and David prepared a total of 7 games, how many minutes did it take for David to prepare all the games?

Question 10:

Samuel slept for 9 hours. If an hour has 60 minutes, how many minutes of sleep did he have?

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Answer Keys

Question 1: 25 minutes

Question 2: 9:15 am

Question 3: 7:26 pm

Question 4: He left 45 minutes later than usual.

Question 5: 600

Question 6: 2 hours and 20 minutes

Question 7: 0:30

Question 8: 4

Question 9: 105

Question 10: 540

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Solutions

Question 1
Chris had to wait for 25 minutes for his appointment as the difference between his arrival time and the appointment time is 25 minutes.

Question 2
Karen's usual bus time is 9:15 am. We can subtract 30 minutes from her taking the bus at quarter to nine, which is 8:45 am. Therefore, her usual bus time is 9:15 am.

Question 3
To solve this problem, we need to add 25 minutes to the time the musicians arrived at the concert hall. One minute past seven is 7:01 pm. Adding 25 more minutes to it gives us 7:26 pm. Therefore, the musicians started rehearsing at 7:26 pm.

Question 4
Dr. Johnson left the office at 6:00pm + 45 minutes = 6:45pm. He left 45 minutes later than usual.

Question 5
The patient had to rest for 600 minutes (10 hours x 60 minutes per hour).

Question 6
To find the duration of training before the water break, we need to subtract the start time from the break time. The start time is 6:00am and the break time is 8:20am, which is a difference of 2 hours and 20 minutes. Therefore, the athletes trained for 2 hours and 20 minutes before taking the water break.

Question 7
Subtract the usual opening time from the actual opening time: 9:30 - 9:00 = 0:30. The supermarket opened 30 minutes later than usual.

Question 8
To convert minutes to hours, we need to divide the number of minutes by 60. Therefore, Mary marinated the pork for 240 / 60 = 4 hours.

Question 9
To solve this problem, we need to multiply the time it takes to prepare each game, which is 15 minutes, by the total number of games David prepared. 15 minutes per game x 7 games = 105 minutes Therefore, it took David 105 minutes to prepare all the games.

Question 10
To find out how many minutes of sleep Samuel had, we need to multiply the number of hours he slept by the number of minutes in an hour. So, 9 hours x 60 minutes per hour = 540 minutes of sleep.