tolong jawab pertanyaan ini!!!

6.A 12/40 x 100 = 30%
B 28/40 x 100 = 70%
7.A 150/200 x 100 = 75%
B 50/200 x 100 = 25%
8.100 - 40 =60/100 x 20 = 12 buah
9.20/100 x 400.000 = Rp. 80.000,00
Maaf kalau salah