Strategies for Comparing Fractions Unit 1 Lesson 4 Strategies for Comparing Fractions

Compare the following sets of numbers using a greater than >, less than < or equal sign =. 456 546 3,200 3,020 99,999 100,000 3 5 4 5

Comparing 3 5 4 5 You can use a visual

However it is easier to use unit fractions! Comparing 2 5 2 7 You can use a visual However it is easier to use unit fractions!

Comparing 2 5 2 7 Both fractions have the same number of unit fractions-which is 2. One fractions has two-fifths, the other has two-sevenths. Which is bigger- a fifth or a seventh? If you had a pizza, would you rather share it with five people or seven people? If you share it with five people you would get a bigger piece, so fifths are larger than sevenths. So two-fifths would be larger than two-sevenths.

How would we compare and There are a variety of ways to compare these fractions, but creating fractions with common denominators is often the easiest way. If we look at these two fractions, one denominator is a factor of the other. If we use 8 as our common denominator, we will only have to change one fraction. After creating two fractions with common denominators, it is much easier to compare the fractions.

How would we compare and One is the only number that is a factor of both numbers. We will need to change both denominators. The product of 5 and 7 is 35, which will work for the common denominator. This method will always work!

How would we compare and Once again we will need to change both denominators. The product of 6 and 9 is 54, which will work for the common denominator. However, we know that both 6 and 9 will go into 18, so that will be a better denominator to use.

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