Which two digits and signs can be interchanged so as to

Solution

Given Equation: 30 + 10 X 5 - 12 ÷ 3 = 33 Interchanging the digits and signs given in option (a), we get: 3 ÷ 10 x 5 – 12 + 30 = 33   0.3 x 5 – 12 + 30 = 33 1.5 – 12 + 30 = 33 19.5 ≠ 33 Interchanging the digits and signs given in option (b), we get: 30 X 12 + 5 - 10 ÷ 3 = 33 360 + 5 - 3.33 = 33 361.67 ≠ 33 Interchanging the digits and signs given in option (c), we get: 30 + 33 ÷ 5 - 12 X 3 = 10 30 + 9.2 - 12 X 3 = 10 30 + 9.2 - 36 = 10 39.2 - 36 = 10 3.2 ≠ 10 Interchanging the digits and signs given in option (d), we get: 30 + 12 x 5 ÷ 10 – 3 = 33  30 + 6 – 3 = 33  36 – 3 = 33  33 = 33