A family spends 30 percent of its take-home income for food, 8 percent for clothing, 25 percent for shelter, 4 percent for recreation, 13 percent for education, and 5 percent for miscellaneous items. The remainder goes into the family savings account. If the weekly net earnings of this household are $500, how many weeks will it take this family to accumulate $15,000 in savings, before interest?