1 1/2 : 2 2/3 : 3 3/4

3/2 : 8/3 : 15/4
= 3/2 × 3/8 × 4/15
= 3/2 × 1/2 × 1/5
= 2/4 × 1/5
= 2/20
= 1/10

1 1/2 : 2 2/3 : 3 3/4 =
3/2 : 8/3 : 15/4 =
3/2 x 3/8 =
9/16 x 4/15 =
36/240 : 3/3 =
12/80 : 4/4 =
3/20.