Yes they are equivalent. You can cross multiple to check and see if two fractions are equal.
For example: 4/12 & 1/3
You take 4 (numerator of first fraction) times 3 (denominator of second fraction) which equals 12
Then you take 12 (denominator of first number) times 1 (numerator of second number) which equals 12
Since both equal 12 they are equivalent