The length of the common chord of two intersecting circles is 12 cm. If the diameters of the circles are 15 cm and 13 cm, then what is the distance (in cm) between their centers?
Sandy and Mandy do (8/13)th part of a work and the rest of the work was completed by Andy. If Sandy, Mandy and Andy take the same work for Rs. 2600, then what is the share (in Rs) of Andy?