Lesson 4 — Activity 1: Fractions in Time



Getting Ready


Have you checked the time lately? If 15 minutes has passed, what fraction have you used to tell the time?

Fifteen minutes is 1/4 of an hour and can be read as "one quarter" or "one fourth" of an hour.

Thirty minutes is 2/4 of an hour or 1/2 of an hour and can be read as "two fourths" or "one half" of an hour.

Forty-five minutes is 3/4 of an hour and can be read as "three fourths" or "three quarters" of an hour.

You are adding and subtracting fractions all day long!


Try This:

What fraction of an hour is 30 minutes?

    30 minutes is 1/2 of

    an hour.



Let's review what we have already learned about fractions!


Now, let's take a look at fractions in our daily life.

If you were to take a job, you would need to follow the instructions of your boss. If she was to tell you that your lunch has been extended to 3/4 (three quarters) of an hour, how many minutes will you take for lunch?

We know that a fraction is part of a whole. A whole hour is 60 minutes. When we divide that 60 minutes by 4 we end up with 15 minutes which is 1/4 of 60.

Therefore, we know that 1/4 of an hour = 15 minutes. Your lunch is 3 x 15 minutes (3/4).

Your lunch is 3/4 of an hour. If 1/4 = 15 minutes, then 3/4 = 45 minutes!

So your lunch is 45 minutes!


Try this activity practicing working with a clock and fractions:

  Self-check!

Try this!


Try this activity where you will practice working with time and fractions. Answer these questions on your own first. When you are finished, click on the tabs below to check your answers.


How many minutes are there between 2:30 and 2:45?

How many minutes are there between 2:45 and 3:00?

How many minutes are there between 3:00 and 3:15?

We know that every 15 minutes is also equal to one quarter of an hour. What do we get if we add 15 minutes + 15 minutes + 15 minutes?

If every 15 minutes is equal to 1/4, then what is 1/4 + 1/4 + 1/4?

1/4 + 1/4 + 1/4 = 3/4 (when denominator is the same just add up top numbers)

Your parents have asked you to clean the garage. You start at 2:30 pm and finish at 3:15 pm. What fraction of an hour have you worked?


Digging Deeper

Click on the Play button below to watch a video on how to read various fractions of time using a clock.