Verbal Reasoning - Mental Ability Questions

A series is given, with one number missing. Choose the correct alternative from the given ones that will complete the series.
400, -200, 100, ? , 25, -12.5

Find the next number in the given series. 9, 11, 15, 17, 21, 23, ?

Introducing a woman, a boy says, "She is the wife of my grandfather's son". How is the woman related to the boy?

Select the appropriate combination of mathematical operators to be sequentially placed between the numbers given on the left of the following equation so that LHS = RHS.

5035 = 20

In a certain code language "TITANIC" is written as "7371835" and "SEMATIC" is written as "6241735". How will "MAINTAIN" be written in that code language?

In a certain code language, 'x' represents '+', '÷' represents 'x', '-' represents '÷' and '+' represents '-'. Find out the answer to the following question.
 
15 x 4 ÷ 35 - 70 + 16 = ?

Some equations have been solved on the basis of a certain pattern. Find the correct answer for the unsolved equation on that basis.

8x7x6=765
5x3x2=421
9x6x4= ?

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

50 + 5 - 700 x 28 = ?