Verified answer

1)-2/5(15а+1/2b )-1/5b=-6а-1/5b-1/5b=-6a-2/5b

2)4 2/5(3/11-a)-1 1/5=1 1/5-4 2/5a-1 1/5=-4 2/5a

3)-1/9(3b-9)+1/3b=-1/3b+1+1/3b=1

4)- 2 3/8*(4c+8/19)+ 9 1/2a=-9 1/2c-1+9 1/2а