An iron conductor and an aluminium conductor are connected in parallel to a supply. The iron conductor is 10 per cent longer than, and half the diameter of, the aluminium conductor. Given that the ratio of the resistivities of iron to aluminium is 40 to 13, find the ratio of the currents in the two conductors.

An iron conductor and an aluminium conductor are connected in parallel to a supply. The iron conductor is 10 per cent longer than, and half the diameter of, the aluminium conductor. Given that the ratio of the resistivities of iron to aluminium is 40 to 13, find the ratio of the currents in the two conductors.