What's the number of the horse weighting 10-5?
CREATE TABLE "runners_and_betting" (
  "starting_price" text,
  "number" real,
  "name" text,
  "age" real,
  "weight_st_lb" text,
  "jockey" text,
  "trainer" text,
  "owner" text,
  "colours" text
);
SELECT MIN("number") FROM "runners_and_betting" WHERE "weight_st_lb"='10-5';