Coding and Decoding Questions

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

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

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

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

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

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

In a certain code language, "TREASON" is written as "RKWWINX" and "POULTRY" is written as "CNXHYKT". How is "NUMBER" 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