Follow BODMAS rule to solve this question, as per the order given below. Step - 1: Parts of an equation enclosed in 'Brackets' must be solved first, and following BODMAS rule in the bracket - Step - 2: Any mathematical 'Of' or 'Exponent' must be solved next. Step - 3: Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated. Step - 4: Last but not the least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated. Given expression is 55 – {(21 – 2 of 3 × 5) + 7 of 2} = ? ⇒ 55 – {(21 – 30) + 14} = ? ⇒ 55 – {– 9 + 14} = ? ⇒ ? = 55 – 5 ∴ ? = 50