Question

Summation problem - see screeshot

Answer 1

$\displaystyle\sum_{i=2}^4\sum_{j=i}^4j^3=\left\{\sum_{j=2}^4+\sum_{j=3}^4+\sum_{j=4}^4j^4\right\}j^3$
$=3\times4^3+2\times3^3+2^3$
$=254$