4 pon + 20 ons =... kg

1 pon = 5 ons
4 pon = 4 × 5 = 20 ons

↪20 ons + 20 ons = 40 ons
↪40 ons = 40 hg = 4 kg ✔

1 pon = 1/2 kg
4 pon = 2 kg

20 ons = 2 kg

Jumlah = 2 kg + 2 kg
= 4 kg