1. 90c : $4.50
2. 80cm : 1.2m

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

1. 22

2. 1

3. 7

4. 18

step-by-step explanation

e2020 got it right

just needed some points but try socratic