To simplify the expression \( \frac{t^{400}}{t^{100}} \) using the Quotient Rule of integer exponents, you can apply the rule which states that:
\[ \frac{a^m}{a^n} = a^{m-n} \]
In this case, \( a = t \), \( m = 400 \), and \( n = 100 \). Thus,
\[ \frac{t^{400}}{t^{100}} = t^{400-100} = t^{300} \]
So, the simplified expression is:
\[ t^{300} \]