Answer :
If by equivalent you mean simplified then it would be 3/7. You can divide the numerator and denominator by 5 to get this.
There's an infinite number of equivalent fractions, but because this number can be simplified, simplification is probably your best answer. The simplified answer is 3/7, which you get by dividing both sides by 5. Other answers include 6/14, 9/21,12/28, and 30/35.