<PRE><B>Question 704429</B>
&lt;pre&gt;

&amp;#8731;&lt;span style=&quot;text-decoration: overline&quot;&gt;54y&lt;sup&gt;21&lt;/sup&gt;&lt;/span&gt;

&amp;#8731;&lt;span style=&quot;text-decoration: overline&quot;&gt;27·2y&lt;sup&gt;21&lt;/sup&gt;&lt;/span&gt;

&amp;#8731;&lt;span style=&quot;text-decoration: overline&quot;&gt;3&lt;sup&gt;3&lt;/sup&gt;·2y&lt;sup&gt;21&lt;/sup&gt;&lt;/span&gt;

Since both exponents 3 and 21 are divisible
by the index of cube roots, which is 3, we
divide the two exponents by 3 and take them
out in front of the radical, and leave just 
the 2 under the radical:

3y&lt;sup&gt;7&lt;/sup&gt;&amp;#8731;&lt;span style=&quot;text-decoration: overline&quot;&gt;2&lt;/span&gt;

Edwin&lt;/pre&gt;</PRE>