What is the Total Orphans number when the number of Total Orphans (AIDS Related) is < 100, and the Maternal (Total) is smaller than 31,000?
CREATE TABLE "populations" (
  "country" text,
  "orphans_as_pct_of_all_children" real,
  "aids_orphans_as_pct_of_orphans" real,
  "total_orphans_total" real,
  "total_orphans_aids_related" text,
  "maternal_total" real,
  "maternal_aids_related" text,
  "paternal_total" real,
  "paternal_aids_related" text,
  "double_total" real,
  "double_aids_related" text
);
SELECT MIN("total_orphans_total") FROM "populations" WHERE "total_orphans_aids_related"='< 100' AND "maternal_total"<'31,000';