Verbal Reasoning - Mental Ability Questions

In a certain code language, '+' represents 'x', '-' represents '+', 'x' represents '÷' and '÷' represents '-'. What is the answer to the following question?

15 - 5 + 25 ÷ 10 = ?

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

19, 28, 39, 52, ?, 84

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

CAL, AWF, YSZ, WOT, ?

Arrange the given words in the sequence in which they occur in the dictionary.
1. Decollete
2. Desecrate
3. Decorous
4. Desipicable
5. Destitute

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

8,24,12,?,18,54

Select the related word/letters/number from the given alternatives.
PEON : QRHS : : JOCK : ?

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

RS, WX, ? , GH

 In a certain code language, “POLIS” is written as “SROLV”. How is “MRUGS” written in that code language?