Elapsed Time Two

What is Elapsed Time Two?

This activity is similar to the Elapsed Time Activity. This activity allows the user to calculate an ending time when the beginning time and elapsed time are given.

Calculating an ending time is an important skill in everyday life. It requires understanding how to read a clock and understanding how we measure time because we don't usually use our traditional decimal (base ten) system to measure time.

For instance, suppose you wanted to know when you would finish your homework and would be able to play basketball with your friends. If you get off the bus at 3:45 every afternoon and you know that you usually have one and a half hours of homework, when will you be done? It's an addition problem but you cannot use the same method for addition that you use if you were just adding whole numbers or decimals:

As is typical with most math, you can think about the problem many ways. Here are a couple of ways:

• You can think about it as an addition problem, but you need to be careful of your place value. Remember that 60 minutes is an hour, not 100 minutes:
• You can think about the problem by picturing the time on a clock and then moving the clock ahead in smaller groups. Start with the minutes, then add the hours:

Related Resources

• Activity Clock Wise
• Activity Elapsed Time
• Discussion about Elapsed Time
• Discussion about Elapsed Time Two
• Worksheet Elapsed Time Two Record Sheet
• Worksheet Elapsed Time Two Record Sheet (doc)

How Do I Use This Activity?

This activity is similar to the Elapsed Time Activity. In this activity, the user will calculate an ending time when the beginning time and elapsed time is given.

Controls and Output

Elapsed Time Two Activity Modes See and Guess: Select the appropriate radio button for the mode you would like to use.

See mode: In this mode the user makes the clock read the correct ending time given by advancing the clock.

• Increment the time on the clock by pressing the 1 Hour, 5 Min and 1 Min buttons.

Guess mode: In this mode the user must determine what time it will be once the given time has elapsed. Once the time is entered, the clock will advance to the time entered. If this answer is correct, then a "Good Job!" message is displayed. If the answer is incorrect the user will be told so and may try again.

• Enter in your guess in the text boxes labeled New Time.

Controls Available in both modes:

• When you've found the correct ending time a "Good Job!!" message will display. If you've gone too far, an "Oops!! Too far" message will display and you will need to press either the Reset button to try the same problem again or the New Time button to try a different problem.
• The Difficulty drop down menu has choices of level 1, level 2, and level 3. On the level 1 setting, all problems will be in one-hour increments. On the level 2 setting, all problems will be in 5-minute increments. On the level 3 setting, all problems will be in 1-minute increments.
• Use the animation drop down menu to select how quickly the clock is animated. Choose from fast, medium, and slow, or choose "Do not animate" if you want to see the result but not watch the animation.
• Each clock at any time can be changed back and forth between a digital clock and a traditional clock with a face. Select the appropriate radio button under each clock for the display you prefer. OR

Scoring

• This activity will automatically record how successful you are at answering the questions. To view the score, press the Show Score button at the bottom of the activity and a pop-up window will appear with the scoreboard. To close this pop-up window press the Close button or click back on the main window.
• To pause the scoring, press the Active button at the bottom of the screen and it will change to a Paused button. To resume scoring, press the Paused button.
• To reset the scoreboard, open the scoreboard using the Show Score button and then press the Reset button.

Description

This activity allows the user to calculate an ending time when the beginning time and elapsed time are given. This activity would work well in groups of one to two for about ten to fifteen minutes if you use the record sheet and five minutes otherwise.

Place in Mathematics Curriculum

This activity can be used to:

• Develop an understanding of addition and subtraction with time
• Develop an understanding of number systems other than base ten
• Help students practice reading a clock

Be Prepared to

• Explain several ways to add and subtract time
• Explain that the applet doesn't show AM or PM times specifically but sometimes the elapsed time and beginning time will be such that they require you to switch from AM to PM

Related Resources

• Activity Clock Wise
• Activity Elapsed Time
• Discussion about Elapsed Time
• Discussion about Elapsed Time Two
• Lesson on Elapsed Time
• Lesson on Elapsed Time Two
• Worksheet Elapsed Time Two Record Sheet
• Worksheet Elapsed Time Two Record Sheet (doc)