URGENT!!! DAU COROANA

1. a = 1 1/4 = 5/4
b = 2/5
a × b = 5/4 × 2/5 = 1/2
2. a = 7/8
a × b = 7/10
7/8 × b = 7/10
b = 8/7 × 7/10 = 4 × 1/5 = 4/5
3. b = 1 1/2 = 3/2
a × b = 5/6
a × 3/2 = 5/6
a = 2/3 × 5/6 = 1/3 × 5/3 = 5/9