hasil dari satu dua per lima

1 2/5 - {(1 4/5 : 0,72) × 75%}
= 7/5 - {(9/5 : 72/100) × 75/100}
= 7/5 - {(9/5 : 18/25) × 3/4}
= 7/5 - {5/2 × 3/4}
= 7/5 - 15/8
= 56/40 - 75/40
= -19/40 (A)