a street has $20$ houses on each side, for a total of $40$ houses. the addresses on the south side of the street form an arithmetic sequence, as do the addresses on the north side of the street. on the south side, the addresses are $4,$ $10,$ $16,$ etc., and on the north side they are $3,$ $9,$ $15,$ etc. a sign painter paints house numbers on a house for $\$1$ per digit. if he paints the appropriate house number once on each of these $40$ houses, how many dollars does he collect?