Since the distance between the chords is greater than the radius of the circle (15 cm), so the chords will be on the opposite sides of the centre.
Let O be the centre of the circle and AB and CD be the two parallel chords such that
AB = 24 cm.
Let length of CD be 2x cm.
Drop OE and OF perpendicular on AB and CD from the centre O.
OE ⊥ AB and OF ⊥ CD
∴ OE bisects AB and OF bisects CD
(Perpendicular drawn from the centre of a circle to a chord bisects it)
