To correct the equation given below, which two symbols should be mutated?
`12 - 8 + 12 xx 9 -: 3 = 9`

Options

A. - and `-:`
B. + and `-:`
C. + and `xx`
D. + and -

Answer

B

Explanation

According to the question,
If we interchange the + and `-:` sign the above equation become correct.
`12 - 8 -: 12 xx 9 + 3` (applying BODMAS)
`implies 12 - 2 xx 3 + 3`
`implies 12 - 6 + 3`
`implies 15 - 6`
`implies 9`
Hence, the correct option is (b)