calculați 1 supra 4 plus 4 supra 5 plus 5 supra 12 plus 3 supra 20 egal

Răspuns :

1/4 + 4/5 +5/12 + 3/20 = 

= (1*15)/(4*15) + ( 4*12)/(5*12) + (5*5)/(12*5) + (3*3)/(20*3) =

= 15/60 + 48/60 + 25/60 + 9/60 =

= (15+48+25+9)/60 = 97/60