Answer:
see explanation
Step-by-step explanation:
Before simplifying the ratios we require them to have the same units.
(1)
$4.50 = 450c, thus
90c : $4.50
= 90 : 450 ← divide both parts by 10
= 9 : 45 ← divide both parts by 9
= 1 : 5
(2)
1.2 m = 1.2 × 100 = 120 cm, thus
80 cm : 1.2 m
= 80 : 120 ← divide both parts by 10
= 8 : 12 ← divide both parts by 4
= 2 : 3
