If '-' means '+', '+' means '×', '×' means '-', then which of the following is not correct?
45 + 9 - 3 × 15 ÷ 2
Answer & explanation
Correct answer: option 3
For option (1)
22+7-3×9= 22×7+3-9
= 154+3-9
=157-9
= 148 = RHS
For option (2)
33×5-10+20= 33-5+10×20
= 33-5+200
= 233-5
=228= RHS
For option (3)
7+28-3×52= 7×28+3-52
= 196+3-52
= 199-52
= 147 ≠ RHS
For option (4)
44-9+6×11= 44+9×6-11
= 44+54-11
= 98-11
= 87 = RHS