8 kg - 30 pon = kg dan 9kg + 5hg + 7dag = gram

1) 8kg - 30pon =....kg
30 pon = 30 x 1/2 kg = 15kg
-> 8kg - 15kg = - 7 kg

2) 9kg + 5 hg + 7dag = .... gram
9 kg = 9x1000 = 9.000 gram
5 hg = 5x100 = 500 gram
7 dag = 7x10 = 70 gram
-> 9.000+500+70 = 9.570 gram

30 pon adalah 30:2 = 15 kg
8 kg- 15 kg adalah -7 kg

9 kg = 9000 g
5 hg = 500 g
7 dag = 70 g
9000+500+70= 9570 g