& of Ryan's socks are blue, & of his socks are green, and the rest are white.

What fraction of Ryan's socks are white?

Let's say Ryan has a total of x socks.

Since & of his socks are blue and & of his socks are green, that means blue socks + green socks would be:
x - (x/3 + x/5) = x - (8x/15) = 7x/15

Now, the remaining socks that are white can be calculated by subtracting the blue and green socks from the total:
x - 7x/15 = (15x/15 - 7x/15) = 8x/15

So, the fraction of Ryan's socks that are white is 8/15.