There shall be provided on the same lot a landscaped open area, not occupied by parking areas or driveways, equivalent to at least 100 square feet per dwelling unit, and provided with walks and benches. Within the landscaped area there shall be provided a fenced area equivalent in size to 25 square feet per dwelling unit, fenced on all sides and with a gate, and equipped with playground equipment suitable for children of five years of age and under.