As 456 is related to 15, in the same way 789 is related to

What is X in the sequence 20, 10, 10, 15, 30, 75, X?

Select the related number from the given alternatives – 4 : 17 :: 7 : ?

Which pair of numbers given in options is similar to the pair of numbers (289, 784)?

The next term in the sequence 4, 10, 22, 46, ..... is -

The missing number (?) in the following series is : 3, 7, 15, 31, 63, ?