Coding and Decoding Questions

If the code for MOTHER is JRQKBU then what is the code for PRINCIPAL?

If "+" means "minus", "x" means "divided by", "÷" means "plus" and "-" means "multiplied by", then 126 x 14 + 7 - 3 ÷ 2 = ?

If 9*4 = 26, 4*4 = 16 and 3*6 = 18, then find the value of 5*2 = ?

If 6#30=5; 8#24=3; 7#28=4; then what is the value of 8#40=?

If, 6x4= 12, 4x12= 24, 12x6= 36 then 6x9= ?

In a certain coding language, 'Ginger is a root' is written as 4123, 'A tree has a root' is 75422 and 'Tree is green' is 385. Which digit represents 'root'?

In a certain code, 592 means 'grapes are sweet', 374 means 'I like oranges' and 267 means 'oranges are sour'. Which digit represents sour?

In a certain code language, "DURING" is written as "GRUFQD". How is "PICKED" written in that code language?