Which of the following groups contains three fractions that are equal?

1/2, 1/4, 1/8

1/2, 2/4, 5/8

2/3, 4/9, 8/27

2/3, 6/9, 12/18

4/5, 7/10, 16/20

Have a look at 2/3, 6/9, 12/18. Note that 12/18 = 2/3, and that 6/9 = 2/3. What is your conclusion?

The fourth group of fractions are all equal to each other: 2/3 is equal to 6/9, if you create a common denominator you will see that they are equivalent. Also, if you created a common denominator of 18 for both, it would be true that it would come out as 12/18. 12/18 can also be reduced to either 6/9 or 2/3, but 2/3 is the most simplified version.