it can't be simplified
4/15 cannot be further reduced.
Not sure about wright, but I would write it as 4/15
four tenths; six fifteenths S. from California
It goes 16/75 times.
One-third is the same as five-fifteenths. Two-fifths is the same as six-fifteenths. Five-fifteenths plus six-fifteenths is eleven-fifteenths. One, or fifteen-fifteenths, minus eleven-fifteenths is four-fifteenths.
8/15 - that is a fraction
4/15 is one fraction. You need at least two fractions to find something in common.
3 fifteenths as a simplified fraction is 1 fifth. All you have to do is divide the numerator and the denominator by the greatest common factor.
7 and 8 fifteenths