🎥 Video solution / Text Solution of this question is given below:
$A = {2,3,5,7,9}$
$y \ge \frac{2x}{3}$
$x = 2 \Rightarrow y = 2,3,5,7,9$
$x = 3 \Rightarrow y = 2,3,5,7,9$
$x = 5 \Rightarrow y = 5,7,9$
$x = 7 \Rightarrow y = 5,7,9$
$x = 9 \Rightarrow y = 7,9$
$\ell = 18$
To make symmetric, elements to be added:
${(5,2), (7,2), (9,2), (5,3), (7,3), (9,3), (9,5)}$
$m = 7$
$\ell + m = 25$