Converting Time to Decimals

Converting Time to Decimals

Author: Teresa Weise

This tutorial should help a student understand how to convert between minutes and decimal parts of an hour, for example, 45 minutes is 0.75 hours (not 0.45 hours).

See More
Introduction to Psychology

Analyze this:
Our Intro to Psych Course is only $329.

Sophia college courses cost up to 80% less than traditional courses*. Start a free trial now.


Step 1: Make a fraction.

What is the decimal for 45 minutes?

(Please don't say 0.45!!!)  

Remember that there are 60 minutes in an hour.  Since 60 minutes = 1 hour, we can create a fraction with 60 as the denominator.

In this case:


Or in more general (algebraic) terms:

m      if m = number of minutes

Once you have a fraction, it is time to convert to a decimal.

Step 2: Converting between decimals and fractions review.

Step 3: Find your answer.


45 = 45 / 60 = 0.75

The answer should be 0.75 parts of an hour,

but what if I divided wrong?  

Better check my work.

Step 4: Using benchmarks to estimate or check your answer

Think back early elementary school when you were first learning about fractions.  Remember when you were first cutting up a circle.  You probably had these pieces.

Fraction Circles



So change these to decimals

Picture 1 shows
1  =  0.25

Picture 2 shows
1  =  0.5

Picture 3 shows
3  =  0.75 


Find your clock (estimate, if needed).

Check your answer!

Since 45 minutes is like the 3/4 clock,

45 minutes = 0.75.

Yes!  That matches the answer from dividing!