Coding and Decoding Questions

In a certain code language, '+' represents 'x', '-' represents '+', 'x' represents '÷' and '÷' represents '-'. What is the answer to the following question?
550 x 22 - 24 + 3 = ?

If SELFIE = LXEYBX, then PHYSICS = ____

If "A" means "plus", "B" means "divide", "C" means "multiply" and "D" means "minus", then 187 B 17 C 4 A 7 D 17 = ?

In a certain code language, “FAINT” is written as “DYGLR”. How is “METRO” written in that code language?

In a certain code language, "RUMOUR" is written as "MURRUO". How is "RACKET" written in that code language?

If "A" denotes "multiplied by", "B" denotes "subtracted from", "C" denotes "added to" and "D" denotes "divided by", then

8 B 31 C 49 D 7 A 16 = ?

In this question, some equations are solved on the basis of a certain system. On the same basis find out the correct answer from amongst the four alternatives for the unsolved equation.

7x6x8=678
8x9x7=987
6x5x7=567
5x4x6=?

If C is coded 3 , DASH is coded as 32 , then DANCE will be coded as