PQ and RS are common tangents to two circles intersecting at A and B. AB, when produced both sides, meet the tangents PQ and RS at X and Y, respectively. If AB = 3 cm, XY = 5 cm, then PQ (in cm) will be
The average of 5 consecutive numbers is 50%, then difference between 'product of largest and smallest number' with 'product of fourth and second number' is