\(\dfrac{10^3+2.5^3+5^3}{55}=\dfrac{\left(2.5\right)^3+2.5^3+5^3}{55}=\dfrac{2.5^3+2.5^3+5^3}{55}=\dfrac{5^3\left(2+2+1\right)}{55}=\dfrac{5^2.5}{11}=\dfrac{5^3}{11}=\dfrac{125}{11}\)
\(\dfrac{10^3+2.5^3+5^3}{55}=\dfrac{\left(2.5\right)^3+2.5^3+5^3}{55}\)
\(\Rightarrow\)\(\dfrac{5^3\left(2+2+2\right)}{55}\)=\(\dfrac{5^3}{11}\)=\(\dfrac{125}{11}\)