Insert one pair of brackets so that this calculation is correct; 3 x 6 + 5 - 1 = 32

3 x 6 + 5 - 1 = 32 
Without any brackets the answer to the calculation would be 22 following the rules of BIDMAS (Brackets, Indices, Division, Multiplication, Addition, Subtraction)

Therefore to make the calculation correct it's necessary to insert brackets around the 6 + 5 so that now the number multiplied by 3 is 11 therefore equating to 33 which becomes 32 when 1 is subtracted from it.

Final answer: 3 x (6 + 5) -1 = 32