3{-1 + 3 [ 7 - 2(-10 + 8)]} Work out ' inside' parentheses first:-
= 3{-1 + 3 [7 - 2*-2]}
= 3 { -1 + 3 [7 + 4]}
= 3 { -1 + 3*11}
= 3 * 32
= 96 answer