( 7 + 2 ) * 9 - 4 = 9 * 9 - 4 = 81 - 4 = 77
7 + 2 * ( 9 - 4 ) = 7 + 2 * 5 = 7 + 10 = 17
9 + 18 : ( 3 + 6 ) = 9 + 18 : 9 = 9 + 2 = 11
( 9 + 18 ) : 3 + 6 = 27 : 3 + 6 = 7 + 6 = 15
( 7 + 2 ) * 9 - 4 = 9 * 9 - 4 = 81 - 4 = 77
7 + 2 * ( 9 - 4 ) = 7 + 2 * 5 = 7 + 10 = 17
9 + 18 : ( 3 + 6 ) = 9 + 18 : 9 = 9 + 2 = 11
( 9 + 18 ) : 3 + 6 = 27 : 3 + 6 = 7 + 6 = 15