In the following question, select the related letters

M/14 : O/12 : : U/6 : ?

Find the missing number by analysing the pattern followed by the numbers in each row.

Select the number from among the given options that can replace the question mark (?) in the following table.

What number should replace the question mark? 

Select the combination of numbers that when placed sequentially in the blanks of the given series will complete the series.

Select the number that can replace the question mark (?) in the following series. 

Find the missing number.

Select the number which can be placed in the column of question mark sign.

F : 216 : : I : ?

What number should come in the place of question mark?