(0.8+(-1/6))+(-21/30)

Question

(0.8+(-1/6))+(-21/30)

Answer 1

       1     2
(0.8-1/6)-21/30=-1/15
1)0.8-1/6=8/10-1/6=24/30-5/30=19/30
2)19/30-21/30=-2/30=-1/15