title: Number of digits after multiplication, dividing
body: <p>I have two numbers <strong>X</strong> and <strong>Y</strong>, i don't know their values but i know that the maximal number of digits that can contain <strong><em>X</strong> is 10</em> (for example) and for <strong><em>Y</strong> is 3</em> (for example)</p>
  
  <p>I need to know the maximal number of digits of <strong>Z</strong> that equals to <strong>X * Y</strong>. Same for <strong>Z = X / Y</strong></p>