7 1/5 = (7*5 + 1)/5 = 36/5 kg (Tom )
36/5 : 12 = 36/5*1/12 = 3/5 kg (Jerry)
36/5 + 3/5 = (36 + 3)/5 = 39/5 = 7 4/5 kg (impreuna)
Răspuns:
Tom=(7*5+1)/5=36/5
Jerry=36/5÷12=36/5*1/12=36/60=3/5
Tom+Jerry=36/5+3/5=39/5=7,8 kg.
