(1*3*5+2*6*10+3*9*15+4*12*20+5*15*15)/(1*2*3+2*4*6+3*6*9+4*8*12+5*10*15)
=[1*3*5(1^3+2^3+3^3+4^3+5^3)]/[(1*2*3)(1^3+2^3+3^3+4^3+5^3)]
=(1*3*5)/(1*2*3)
=5/2
(1*3*5+2*6*10+3*9*15+4*12*20+5*15*15)/(1*2*3+2*4*6+3*6*9+4*8*12+5*10*15)
=[1*3*5(1^3+2^3+3^3+4^3+5^3)]/[(1*2*3)(1^3+2^3+3^3+4^3+5^3)]
=(1*3*5)/(1*2*3)
=5/2