Exploring Time Intervals: Start and End Times

This video tutorial covers how to calculate start and end times using time intervals. It explains the use of number lines and analog clocks to determine elapsed time. Through examples like Tim's homework and Raj's swimming, the video demonstrates finding both start and end times. It also includes a detailed example with Emma and Tala's homework to calculate elapsed time. The tutorial concludes with a preview of the next lesson on word problems involving elapsed time.

What can help us find an ending time?

• A calendar

• A number line

• A digital clock

• A stopwatch

How do we find a starting time given the ending time and elapsed time?

• Use a digital timer

• Guess and check

• Count backward on a number line

• Count forward on a number line

What increments can we skip count by on a number line?

• 10 minutes

• 1 minute

• 5 minutes

• All of the above

At what time did Tim finish his science homework?

• 5:14 PM

• 5:10 PM

• 5:00 PM

• 4:44 PM

How do we use an analog clock to find an ending time?

• Counting forward by hours

• Skip counting by fives and then by ones

• Using the second hand

• Only counting by ones

What time did Raj start swimming?

• 12:50 PM

• 1:15 PM

• 1:40 PM

• 12:25 PM

How do we find a starting time using an analog clock?

• Counting forward until the minute hand reaches the end time

• Moving the hour hand backward

• Counting backward by jumps of five

• Setting the clock to the end time and adding minutes

What was the elapsed time for Emma and Tala's homework?

• 50 minutes

• 60 minutes

• 54 minutes

• 44 minutes

How can we quickly estimate elapsed time close to an hour?

• By adding minutes to the start time

• By counting back the minutes less than an hour

• By using a stopwatch

• By guessing the time

What method can be used to find the start time if the elapsed time is nearly an hour?

• Counting back the minutes less than an hour

• Subtracting from 60 minutes

• Counting forward from the end time

• Using a digital clock