5 1/3-(1/10+2/15):1/25

5 1/3 - ( 1/10 + 2/15) : 1/25
= 5 1/3 - (3/30 + 4/30) : 1/25
= 16/3 - 7/30 x 25/1
= 16/3 - 175/30
= 160/30 - 175/30
= - 15/30
= - 1/2