Verbal Reasoning - Mental Ability Questions

The following equation is incorrect. Which two signs should be interchanged to correct the equation?

5 + 8 ÷ 40 - 20 x 25 = 6

Night blindness : Sight :: ___ : Speech 

In the following question, select the related word pair from the given alternatives.

Gold : Jewellery : : ? : ?

Select the related word/letters/number from the given alternatives.

523 : 325 : : 603 : ?

In the following question, select the related number from the given alternatives.

11 : 16 : : ? : ?

Select the related word/letters/number from the given alternatives.

Traditional : Modern : : Sharp : ?

In the following question, select the missing number from the given series.

42, 21, 21, ?, 63, 157.5

In the following question, select the related word pair from the given alternatives.

Square : Perimeter : : ? : ?