Coding and Decoding Questions

If SYSTEM is written as RXRSDL.
How can CORRECT be written in that code?

If "-" means "plus", "x" means "divide", "÷" means "multiply" and "+" means "minus", then 26 + 400 x 20 – 21 ÷ 12 = ?

In a certain code language, "SINGING" is written as "TJOHJOH". How is "DANCING" written in that code language?

If FRISKED is coded as HTKUMGF, then how will SUN be coded as?

If "+" means "minus", "x" means "divided by", "÷" means "plus" and "-" means "multiplied by", then
300 x 10 – 5 + 36 ÷ 57 = ?

In a certain code language, “TRAP” is written as “53” and “MADE” is written as “21”. How is “LATE” written in that code language?

The following equation is incorrect. Which two signs should be interchanged to correct the equation? 12 - 6 x 5 + 20 ÷ 4 = 31

If CROWNED is coded as APMULCB, then how will TAP be coded as?