Which Fraction is Greater?

by Michael_Koger

There are occasions when one will encounter more than one fraction, and the question will arise—which of two fractions is the larger?

When one compares more than two fractions, the query is—which is largest?

Suppose that a student has to compare two fractions. The assignment requires that he or she list them in order from smaller to larger. Here are two fractions: ⅙ and ³⁄₇.

If one has worked with fractions a lot, it may appear that they are already in proper order. Specifically, ³⁄₇ is only a little less than ½ because 3.5 is, in fact, half of 7. The other fraction, ⅙, is much less than ½ and is therefore the smaller of the two.

Least Common Denominator

If, however, the student is not able to see this, then it is possible to demonstrate mathematically which one is larger.  This entails the use of the least common denominator [1].  The denominator in ⅙ is 6, and it is the product of (3)(2)=6.  The denominator of ³⁄₇ is 7, and since it is a prime number, it is merely the product of (7)(1)=7.

One may notice that the product (6)(7)=42.  In other words, the product of our two denominators gives the least common denominator in this instance.  The next step, therefore, is to make the denominators of both fractions equal to each other and then add the two numerators [1].

A simple approach to do this is to multiply ⅙ by 7/7.  This is the same as multiplying ⅙ by 1, and the result will be 7/42.

Next, one can multiply ³⁄₇ by 6/6, and again, it is no different than multiplying ³⁄₇ by 1.  The result is 18/42.

The student returns, therefore, to the question--which is larger?  The comparison is between 18/42 and 7/42, and obviously 7/42 is smaller than 18/42.  However, one already knows that 7/42 is the same as ⅙, and 18/42 is equal to ³⁄₇.

Hence, the proper order of the two initial fractions from smaller to larger is:  ⅙ and ³⁄₇.

Another approach is to plot the two fractions on a number line and determine which is greater.  In some instances, the student will discover that two fractions are in fact equal to each other, and the number line or least common denominator method will lead to the same result [1].

Conclusion

Fractions may be equal or unequal to each other.  In either case, the least common denominator approach or use of a number line will yield the correct answer to that question.

References

  1. Khan Academy.  (2016).  Comparing and ordering fractions.
  2. The photo is from Massachusetts Institute of Technology.
Updated: 02/02/2017, Michael_Koger
 
Thank you! Would you like to post a comment now?
2

Comments

Only logged-in users are allowed to comment. Login

You might also like

What's in Your Junk Drawer?

Everyone has a junk drawer. It is where we put the missing caps to the marker...

First Grade Math Games - Various types Check them out

If your kid learns to love maths in the first grade, then surely there wouldn...

Math Help for Kids: Make it Fun

Teaching math can be challenging, as kids quickly lose interest in the lesson...


Disclosure: This page generates income for authors based on affiliate relationships with our partners, including Amazon, Google and others.
Loading ...
Error!