30−[26−{15+(8−¯¯¯¯¯¯¯¯¯¯¯¯6−3)}]×815÷49×34−12+1
=30−[26−{15+(8−3)}]×815÷49×34−12+1...........[removing vinculum] ...(0.25 marks)
=30−[26−{15+5}]×815÷49×34−12+1..................[removing small bracket] ...(0.25 marks)
=30−[26−20]×815÷49×34−12+1..................[removing curly bracket] ...(0.5 marks)
=30−6×815÷49×34−12+1..................[removing square bracket] ...(0.5 marks)
=30−6×65×34−12+1.................. [division] ...(0.5 marks)
=30−5410−12+1.................[multiplication] ...(0.5 marks)
=31−5410−12...........[addition] ...(0.5 marks)
=310−54−510...................[subtraction] ...(0.5 marks)
=25.1 ...(0.5 marks)