Coding and Decoding Questions

In a certain code language, "OPTIMIST" is written as "LKRNRGHG". How is "PESSIMIST" written in that code language?

If S = 19, SUN = 54 and CAKE = 20 , then MISTAKE = ?

If REGAINS is coded as QDFZHMR, then how will PRY be coded as?

If "+" means "minus", "x" means "divided by", "÷" means "plus" and "-" means "multiplied by", then
76 x 4 + 4 – 12 ÷ 37 = ?

If P denotes ÷ , Q denotes x, R denotes + and S denotes ­ then what is the value of 18Q12P4R5S6

If 5 # 9 @ 7 = 52 and 3 @ 9 # 2 = – 89, then 7 # 6 @ 9 = ?

In a certain code language, '-' represents 'x', '÷' represents '+', '+' represents '÷' and 'x' represents '-'. Find out the answer to the following question.

9 ÷ 12 - 15 + 4 x 10 = ?

If ENTRY is coded as 98462 and STEADY is coded as 749312, then how is NEATNESS written in that code?