Verbal Reasoning - Mental Ability Questions

In the following question, select the related letters from the given alternatives.
PRAG : QTDK : : STOP : ?

Which set of letters when sequentially placed at the gaps in the given letter series shall complete it?

_r_r_t_r_r_t

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

13 - 14 + 15 x 70 ÷ 14 = ?

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.

13,25,49,85, ?

If 'HARBOUR' is written as 'IBSCPVS' , how is 'HABITAT' written in that code?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

RTM, QRJ, PPG, OND, ?

If "#" means "subtraction", "&" means "division", "@" means "addition" and "%" means "multiplication", then 315&3#9@4%6 = ?

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