Question

2730:(1+2+3+....+20) si. 15720:(1^2+2^2+3^2+4^2)

Answer 1

2730:(1+2+3+....+20)= 2730 : (20*21):2= 2730 :(10*21)= 2730: 210= 13 . 15720:(1^2+2^2+3^2+4^2)= 15 720 :( 1+4+9+16)= 15 720 : 30 = 524.