2 1/2 – 2 2/5 : 1 1/2

Penjelasan dengan langkah-langkah:

= 2 1/2 – 2 2/5 : 1 1/2

= 5/2 – 12/5 : 3/2

= 5/2 – 12/5 × 2/3

= 5/2 – 24/15

= (75 – 48)/30

= 27/30

= 9/10