Tolong jawabkan no 1,3,5

1. bangunan : 27 => x
jembatan : 18 => 12

27/18 = x/12
x = (12 . 27) / 18
= (2. 27) / 3
= 2. 9
= 18

3. 3/3,5 = 150 / x
x = (3,5 . 150) / 3
= 3,5 . 50
= 175