Question

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Answer 1

Hey there! :D

Let's keep the fraction 5/7 in mind. We should be able to reduce everything to 5/7. 

15:21 (divide both by 3) you get 5:7. That is equivalent. 

10 to 14. Divide both by 2. 5 to 7. That is equivalent. 

The correct answer is 28/20. That is not equivalent. 

I hope this helps!
~kaikers