I have no idea by just looking at them, so I change the fractions to a common denominator by using a form of one. 45 is common here.
5*4/5*9 = 20/45
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3*7/3*15 = 21/45
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We see that 7/15 is just greater than 4/9.
What is smaller 4/9 or 7/15?
