Question

{[1+(1/5-2):3]:(2/3-1)}

Answer 1

{[1+(1/5-2):3]:(2/3-1)}
{[1+(1-10/5):3]:(2-3/3)}
{[1+9/5:3]:1/3}
{[1+9/5.1/3]:1/3}
{1+9/15:1/3}
1+9/15.3/1
1+27/15
15+27/15=42/15

espero ter ajudado!!!