tolong di jawab pakai cara ya kak !!!!!! pleaseeee

semuanya dikali silang
1. 180/20
2.540/60
3.120/480
4.720/30
5.60/16
6.80/625
7.168/50
8.525/200
9.20/500
10.75/700
11.300/16
12.4800/1200
13.25600/16000
14.1000/300
15.3200/600