3.5kg+45ons+2500gram =…..kg

1 ons=0.1 kg
2500g=2.5 kg
45 ons=4.5

3.5+4.5+2.5=10.5 kg

3,5 kg + 45 ons + 2500 gram =… kg
= 3.5 kg + (45 ons : 10) + 2500 gram
= 3.5 kg + 4.5 kg + (2500 gram : 1000)
= 3.5 kg + 4.5 kg + 2.5 kg
= 10.5 kg