Answer:
2.5 : 1
Explanation:
(1) 150 : 60 ← divide both parts by 10
(2) 15 : 6 → ( not 100 : 60) ← divide both parts by 3
(3) 5 : 2 ← divide both parts by 2
(4) 2.5 : 1
5.9m questions
7.8m answers